Having international experience early in your career is a plus that will set you apart. But keep expectations low; don't anticipate payment or benefits. Agencies look for passionate creative hippies like you, so go find the opportunities.
Here are some tips for doing that:
1. Search for agencies. Start searching for agencies on all continents -- you can find lists of agencies on various websites. If you're a creative looking for a good portfolio, a good starting point could be The Gunn Report that will help you make a list of the most awarded agencies in the world.
2. Be careful what you fish for. Of course you should aim for the top but be realistic. So unless you are completely sure your portfolio will knock out the creative director, you should build your way to the top agencies, by gaining experience elsewhere first.
3. Devise a three-year plan. It's difficult to plan ahead at this age but try to; it's crucial. Plan where you want to start your advertising experience and where you want it to end. Of course, there will be detours along the way but you should always have a career map drawn in your mind, including locations and potential employers.
4. Address to impress. You should always be creative when sending your application. Just an e-mail with a link to your portfolio won't do. Creative directors are good profilers but they can't read minds, so you should be able to prove not only that you can do the job, but that you really love the agency. First research the shop and the people, and then approach them in a unique way. Customize your application for each agency. Consider it your first pitch for a major account and prove your original thinking.
When I entered advertising I created as my application a short movie of how I viewed advertising and what I believed I could do. Be creative and don't imitate what others do; just because one strategy worked for a friend doesn't mean it will work for you, too.
After a couple of years in different markets, you'll be more experienced on international accounts and have an exquisite portfolio. Then, not only will you feel like a million dollars, but you'll hopefully earn some of it, too.