A few benefits of having international work experience are:
1. You're more culturally sensitive than the next person
Many companies do business internationally, and even if you start working at one that doesn't have an international presence, you will still have customers and colleagues from other countries.
Since you have international work experience, you're going to be better equipped to deal with any cultural differences that you run into in the workplace. This will make your application look better than that of someone who has never worked or lived abroad. Employers want to create a safe and fun working environment, and this means that they must hire employees that are culturally sensitive (AKA - people that have experience interacting with people from diverse backgrounds).
2. You have better communication skills
Another benefit that comes with international work experience is that you're able to communicate with all types of people more effectively than your coworker that's never left the country. Employers place a lot of value on effective and clear communication, so guess which one of you will be put up for promotion first.
After spending a year or more communicating with people that don't speak English as their first language, you will have learned how to effectively communicate with people that speak different levels of English. The same thing goes for people that worked internationally somewhere where English is the native language -- there are still cultural nuances and barriers that must be overcome to effectively communicate with the people around you.
3. Speaking multiple languages is a valuable skill
Not everyone with international work experience will be able to speak multiple languages, so if you did manage to learn another language while abroad, this is a huge advantage for you. When you come back from working abroad, many prospective employers will want to hire you if you can speak more than one language. This skill allows you to communicate with potential clients, customers, and colleagues that aren't native English speakers.
Having learned a language while abroad also shows that you're committed and determined, as it's not an easy thing to do!
4. International work experience says a lot about your personality & skills
Even if you aren't fluent in another language when you come back home from your time abroad, the international work experience that you amassed says a lot about you. It says that you're adventurous, independent, self-reliant, adaptable, open-minded, patient, and tolerant, among many other things. These are some of the personality traits that many future employers in your home country will be looking for in an employee, so you're in luck!
5. You have more life experience than most other people
Traveling, teaching, and working abroad all give you great life experience that not everyone gets to put on their resume.
After working abroad, you've seen more of the world, met new people that are different from yourself, networked internationally, and tried new things. All of this adds up to some great life experience that you can use to make future decisions, which will positively impact you both in the workplace as well as in your social life.
How to gain valuable international work experience:
There are many ways to get international work experience and teaching abroad is one of the most popular. Even if you've never taught before, you can take a TEFL course and start teaching English abroad whenever you'd like.