Travel Tips
If you're planning on visiting many countries, and why wouldn't you, then you really need to have your head screwed on when it comes to visas.
If you're lucky enough to come from a country where you can travel, for the most part, freely, then it really isn't that difficult to sort out your visas.
Passport
The first thing you should have, and this should be pretty obvious, is an up to date passport, they say with at least 6 months left, I say at least a year.
Here's a tip, take a picture of your passport and email it to yourself, in fact, you should do this for all your important documents, no need to be printing out copies.
Photos
You'll need passport photos for those countries where you cant get a visa on arrival, no biggie, it's better to get these when you're away, usually works out cheaper.
Plan it
If you're in Thailand, for example, and are planning on heading into Vietnam overland, you'll need a visa. You should really take care of this while you're in Bangkok, although, like me, you can take care of it if you're not. I used a travel agent for my Vietnam visa, it was motorbike couriered to Bangkok, took a few days, and cost me more. More risky, timely and costly, so, if you can avoid doing this, you really should.
Visa's From Your Home Country
Some countries require you to get a visa from your home country, Russia for example. If you're planning on heading there, sort it before you go. Can't really be helped when you're on the road.
Also, if you're planning on heading to China, you only get a 1-month visa from Hong Kong, as apposed to a 3-month visa from your home country. There are, of course exception countries, for example, Indian, where you can only get a one-month visa at a time.
Cost
Visa costs will vary, depending where you're from, for example, a 3-month L holiday Chinese Visa will cost an Irishman roughly $30, the same visa will be around $100 for someone from the U.S.
If you have dual citizenship, find out the cheaper option.
If you'd like some more easily digestible advice on backpacking, or to read some of my tales from the road, head on over to my blog, http://www.planitbackpacker.com/
There's lots of things I could have done better when I first set out on the big solo backpacking adventure. You learn by your mistakes I guess. If you're new to backpacking, why not learn from mine.
Happy Backpacking!