If you're near an ocean or other large body of water, head straight to it and the work is usually done for you. Coastlines are among the prettiest and most accessible places to set up a wild camp. If you can, follow the shore until you're away from whatever public access you came in on - but if you set up near the water be sure to keep the tides in mind.
If you're inland, check your map for lakes, rivers or patches of green with minor roads running through them. Once you've located a possible candidate for a night of free camping, don't stop there - as you walk, ride or drive, look for even smaller unmarked trails leading deeper into the woods. Braving a small river crossing can be an effective way to find an even wilder spot.
Failing all of these options, a small patch of farmland, a church courtyard, or a cemetery are all excellent options. Though many balk at the idea of camping in a cemetery, they are often a perfect place to spend the night. It's very unlikely you'll encounter people there, and many have water spigots for watering the flowers that you could use for cooking, cleaning and perhaps drinking.
If you're going to cook at your wild camp, make sure you have lots of water. If you know you are camping on private property (it's often hard to be sure), asking for permission is recommended. You will be hard pressed to find someone that will turn you down - in fact, once you've swallowed your pride and done it, you may well discover this is a great way to meet the locals.
Some countries have laws colloquially referred to as the "right to roam". The spirit of the idea is that we all have a right to respectfully travel through the world, regardless of who owns the land we are on. When visiting a new country, it's a good idea to investigate these rights - they can make the task of finding a place to sleep immeasurably easier, especially for first-time wild campers.
As you become a confident wild camper, relying on the availability of the accommodations in the areas you visit will become a thing of the past. You'll enjoy an unprecedented amount of flexibility over traditional methods of travel. Coming and going as you please in unfamiliar lands, discovering your own unique and secluded destinations as you go, this is the stuff adventures are made of.
Tyler Kellen is co-author of Going Slowly. He writes his blog with wife, Tara, chronicling their adventures around the world by bicycle.