I've done this in the past, and planning on doing it a lot more in the future. My last trip I spent unicycling across Thailand.
I think one of the bigger factors for me is having a nest-egg to rely on when shit hits the fan and there is no work.
Having a decent sum saved up in the bank and investing it all as a fall-back when you are stuck in a forest in the middle of nowhere or in a hospital with an infection in some random 3rd world country that has no antibiotics will help.
I only have experience traveling in SE Asia (Indonesia, Vietnam, Thailand, Malaysia), but there are jobs for foreigners everywhere. Teaching a sport / bringing tourists on adventures (rock-climbing, mountain biking, hiking, photography trips), working in hostels as a front desk help, helping local businesses with their websites, working on a farm (check out HelpX and WOOFing), or tutoring English / math in a local school...
Most of these gigs won't save you money on the road, but they may allow you to travel for free and break even. Couch surfing is definitely a big one to save money. There is also the route of bringing a laptop and working odd freelance jobs like writing travel articles, photography gigs, Amazon Turk...They won't pay much, but you really only need $5-10 / day traveling in some SE Asian countries.