here's a few ways from my experiences around the world
cutting hair for tourists who don't want to go to a third world barber
the oldest way to travel buy something cheap somewhere sell it for profit somewhere else
example also is to be your own best advertisement like this sexy italian girl would go to brazil buy suitcases full of those tiny thong things they wear in rio then she would wear them on the beach in tourist places and all the tourist girls would want to buy one ... get the idea
photo journalist have camera can travel
become a professional gambler poker backgammon etc
you'll like this next one true story a couple travelled the world in their yacht for years and while at sea made kites then pulled into anywhere they went husband would start flying the kites people children tourists would flock and want one wife sells them and ta da
I have been travelling all my life, and met many people in different countries al over.
I'm also going to India in a month time, although i only have £3000 saved up, this isn't a bad thing however. In many of the countries outside of Europe prices are much lower than our own! In India, you can stay for free if you visit, monasteries or temples. Staying in hostels and eating cheaply can be done for £5 a day.
Many of the places you visit will be dictated by cost of travel and also visa rules. I can only stay in India for 6 month (max visa length) then after Im going to New Zealand to work, earn another £3k then travel to South America.
This is usually the way i like to travel and many other do also. If you can save as much as possible £10k for example, would mean you could travel in many countries without the need to work. Which for some is more appealing.
This is a very brief answer, but your journey is very personal and should be unique to you. You can work it out, with little or lots of money!
Look for work on the cruise liners is the best way.
Cleaners, cooks, shop assistants, entertainers, bar tenders.
Long hours not much rest in between, pay i know not.
Another way is as a child minder to a family with you only paying a little part of your fare.
The other way is back packing and begging your way round.
They don't, unless they inherit a fortune