Most people know that you can book a free flight by using frequent flyer miles. And if you have enough frequent flyer miles, then you can even fly first class for free. Of course, the only problem is that it’s really hard to accumulate a lot of miles by flying.

Luckily, there is a way to get hundreds of thousands of frequent flyer miles without flying at all.

The good news is that credit card bonuses work just as well for normal people like you and me. By simply getting 1 or 2 new cards, you can get enough frequent flyer miles for multiple round–trip flights.

There is no need to go crazy and get 15+ new cards. Of course, if you did, then you could literally earn enough miles to fly around the world multiple times.

1. Use A Business & First Class specialist

This tip is really quite simple. Don’t immediately book through the airline’s website direct. Price up an aggregator like Skyscanner and price up the same flight on the airline website direct. Then speak to a flight expert and respectable Business Class specialist consolidator like Sojourn Flights, who can usually quote cheaper rates for Business and First Class flights than the ones you find online.

2. Upgrade using your miles

You may not have enough miles for a Business Class flight, but if you book in the class below your preferred seat, you may be able to upgrade your ticket using your air miles or points. British Airways is one of the airlines with the best frequent flyer program when it comes to using your miles for an upgrade. Using British Airways miles -called Avios – to upgrade one class (from Economy to Premium Economy, from Premium Economy to Business, or from Business to First) is one of the best ways to spend them. It usually requires around 25,000 Avios to upgrade a cash booking to the next cabin on a longhaul flight (when there’s availability of course). Avios can be used for an upgrade on British Airways, Iberia and American Airlines flights.

As an example, if you want to fly with British Airways in Business Class London to New York, you can book a Premium Economy ticket, and then login to “Manage My Booking” on BA.com select your flight and choose to ”Upgrade this flight with Avios”. If there is reward availability British Airways will tell you how much it will cost. In this example, an off-peak reward flight in World Traveller Plus costs 26,000 Avios; an off-peak reward flight in Club World costs 50,000 Avios. Therefore the cost to upgrade this flight using Avios is 50,000-26,000 = 24,000 Avios. If you booked your ticket through a travel agent, you will need to check with them to see if your booking can be upgraded with Avios. Alternatively, if you are ready to book and do not yet have any tickets for your trip, you can use the BA.com ‘book and upgrade’ form to search for availability and get a price for booking and upgrading at the same time.

Even if you don’t have enough miles for an upgrade, don’t despair. If you are running low, consider converting your hotel points over to airline miles to boost your balance. Many airlines also offer a part-buy miles-flight option where you can pay to buy in the miles that you need as you book your redemption ticket.

3. Upgrade at the last minute

You can pick up a cheap upgrade at the last minute if a cabin is under-booked. In this option you would have to book an Economy or a Premium Economy ticket and you would have to be prepared to fly in Economy or Premium Economy if you cannot find an upgrade. But equally, this method is probably the cheapest way to travel in Business Class as long as you have lady luck on your side. To get a last minute upgrade, you must keep checking the airline website or app the week before your flight. On BA.con the ‘manage my booking’ page will show you the availability of upgrade deals. If this doesn’t work, don’t give up. It is then worth asking if any paid upgrades are available as you check in. Airlines want to monetize every last seat, so they will try to sell you any unsold Business Class seats if they are available.

4. Book sale tickets

Most airlines offer sales from time to time and if you add yourself to their mailing lists, then you will be notified when they have a sale. For example, British Airways often has sales where they allow you to book a Business Class return trip and fly one leg in First Class. Qatar Airways often launches 2-for-1 sales where your companion will travel for free when you buy one Business Class ticket. And occasionally, Swiss launches sales with First Class fares that are cheaper than Business Class.

5. Book unusual routings

Consider flying to and departing from other airports to snag a cheaper Business Class flight. For Example, Etihad Airways is often cheaper out of continental airports than out of London when flying to the same destination.

6. Consider other airlines

Finnair offers an excellent and well priced Business Class product to Asia; WOW air is the cheapest way to fly between American and Europe (although not an awfully comfortable way to fly); and Qatar Airways also offers a great Business Class product (and often the lowest Business Class prices) to the Middle East and Asia.

7. Book Early

Converse to my advice above in point 3. You should upgrade at the last minute, but book your flight as far ahead as possible or during sales. Time is the key to get the best Business & First Class deals as the prices are very high when you need to make a last-minute booking.

8. Book flights at unpopular times, days and seasons

Avoid school holidays and weekends on sunny short-haul routes. For long-haul flights landing in major hubs like New York, Hong Kong and Singapore, school holidays, particularly August, tends to offer a cheap time to fly as there are less travellers flying for business in August. Travel to cities during weekends in the summer holidays. Paris empties out in August with the French going on holiday, making this a comparatively quiet and cheap time to travel to and visit Paris.

9. Be open to offers from the airline

If your flight is delayed, cancelled or overbooked, let the airline agents know that you are happy to wait a day or two to fly out or return, in return for an incentive. For example, if you are booked into Economy Class, the airline may offer to cover your hotel AND upgrade your seat in return for taking a later flight. Economy to First is not unheard of in this situation.

10. Bid against other passengers for a premium seat

Plusgrade and Optiontown collaborate with some of the world’s best airlines to offer passengers the opportunity to upgrade their travel experience. This is how it works: after you’ve booked your flight on the airlines’ website, you’ll be invited to make a bid to upgrade to the next cabin from your booking confirmation page and confirmation e-mail. All you have to do is to enter a bid price to upgrade each leg of your flight, along with your credit card information.  Between 72 and 24 hours prior to departure, the airline will notify you via mail if your request for an upgrade has been approved or not. If your upgrade offer has been accepted, your credit card will be billed with the amount you offered, and you will receive your upgraded boarding pass. If your upgrade offer hasn’t been accepted, you pay nothing and keep your original ticket.

Once you know the deals to apply for, the 3–step process looks like this:

1. Apply for a new credit card that has a big frequent flyer mile bonus.
2. If necessary, spend the minimum amount to get the bonus. Many cards have no spending requirement.
3. Redeem your miles and fly anywhere.

Now for the insider info:

Emirates First-Class Suites

How to book it for less than coach: Emirates may not partner with the large airline alliances, but it does offer valuable points partnerships that are easy to leverage. Those include American Express Membership Rewards and Starwood Preferred Guest, whose points can be applied toward an award booking through the Emirates website. A first-class ticket between Dubai and Europe costs 85,000 miles each way.

Have a Chase Ultimate Rewards account? Transfer points from there to Korean Air’s Skypass program, which partners with Emirates, and your round-trip Dubai-to-Europe ticket will cost 120,000 miles. If you have Starwood Preferred Guest points to burn, try moving them to Japan Airlines Mileage Bank, which charges just 100,000 miles for a round-trip between Dubai and Brussels, Geneva, or London.

The caveats: Taxes and surcharges on award tickets can run you more than $1,000, and award space in Emirates’ new first-class suites is virtually nonexistent—at least for now. As more planes with the new suites go into service and the hubbub over their launch dies down, that should change.

Singapore Airlines First-Class Suites

How to book it for less than coach: The only miles currency that Singapore Airlines accepts for first-class bookings is its own KrisFlyer miles—a transfer partner of American Express Membership Rewards, Chase Ultimate Rewards, Citi ThankYou Rewards, and Starwood Preferred Guest. Even a new KrisFlyer member can score the 75,000 miles it takes to fly one-way in a suite from Singapore to Sydney by rolling over the same number of points from one of these partner programs.

The caveat: Limited availability, as with Emirates. Review frequent-flier boards such as FlyerTalk and the blogs of Boarding Area to stay up to date as availability loosens up on both products.

Air France la Première

How to book it for less than coach: As one Air France flight attendant told me on a recent trip, “There are no upgrades to la Première.” The airline doesn’t make it easy to get it free by using miles, either, but it is possible. To do so, you can use only Air France’s Flying Blue miles—and solely if you have elite status with the airline. The good news is, you need only a basic level of elite status to be eligible, so frequent fliers can credit a few weeks or months of travel to Flying Blue and they will be set. Flying Blue also transfer partners with American Express Membership Rewards, Chase Ultimate Rewards, Citi ThankYou Rewards, and Starwood Preferred Guest, so it’s easy to pad your account with points from other programs.

The caveat: Brace yourself for high redemption rates. Flights between Paris and the U.S. will cost 200,000 miles each way, while flying from Paris to one of the airline’s Asian destinations will cost 320,000 miles each way. Taxes and fees in either direction can also cost several hundred dollars.

Cathay Pacific First Class

How to book it for less than coach: Transfer agreements with American Express Membership Rewards, Citi ThankYou Rewards, and Starwood Preferred Guest make it feasible to book even the Apartment as an award ticket. All you have to do is shuffle points into an Etihad Guest account and redeem directly through the airline’s website. Redemption rates vary by destination, but a one-way award ticket from JFK to Abu Dhabi costs roughly 136,500 Guest miles, plus $275 in taxes and fees. A similar ticket between Abu Dhabi and London costs far less: about 88,000 miles, plus $235 in taxes and fees.

Prefer to use AAdvantage miles? You can do that, too. A first-class award between Abu Dhabi and the U.S. costs 115,000 miles each way, and routes between Abu Dhabi and Europe come to about half that.

The caveat: Domestic customer support at American Airlines is wonky about redeeming flights on Etihad. As a result, you’ll have to call one of American’s international call centers, such as the one in Australia, to book with AAdvantage miles.

Bonus: French all-business-class startup Lola Compagnie definitely isn’t your average airline. The planes are exclusively business class, with 74 lie-flat seats, and the usual full-price, round-trip ticket across the Atlantic is about $1,900. That fare sometimes beats out economy on traditional airlines and looks like pocket change compared to the usual $3,000 (or upwards of $8,000) for an average business class ticket.