Have a Plan -- Don't Be Naive
Thirty years ago, if a college student came home and announced that he or she was going to major in, say, Spanish, the parents might have hit the roof. What possible job can you get with that degree? Things have changed a lot -- but a degree in a foreign language all by itself is probably not the best plan -- unless you plan to teach or have your own business in which it can be of use.
The first thing any student needs to do with any major is take study seriously. Learning a foreign language after puberty is very hard work -- but it is possible. The post-adolescent brain likes to analyze and find structure deliberately -- this can be put to efficient use. A talented person can become quite proficient after a couple of years of intense study. But what is intense study? I mean six to eight hours a day, five or six days a week, total psychological immersion (geography has less to do with language learning than many people suppose).
Let's assume a student is quite proficient, is a sophomore or freshman in college and plans to declare a major in a foreign language. He or she should also ask themself other questions, such as what type of work he or she wants to do. Career planning and counseling offices have tests to show what sorts of careers a person might be best suited for and enjoy. Future salary expectations and an idea of where one wants to live are also important.
Nowadays, any major combined with Spanish will give a college graduate an advantage in job searches. A bilingual health care worker of any kind can go practically anywhere and find employment. A specialized nurse, for instance, one in pediatric ICU who knows Spanish, can almost write his or her own paycheck.
Majoring in a second language and some other subject is smart, but it still isn't enough. It is essential to acquire the vocabulary of the other major so that you can function professionally in your acquired second language. There are many discipline-specific bilingual dictionaries out there: medical, legal, financial, engineering, etc. When I lived in Washington, DC, I discovered a terrific bookstore for obtaining all my technical dictionaries: Reiter's Books.
If you haven't already begun a second language (say, in high school), or perhaps even if you have, it is important to think strategically about the advantages or disadvantages of your particular combination. A music major would be wise to study Italian. A person studying in a culinary school would be smart to study French. A person studying petroleum engineering would be smart to study... Arabic. The point is, don't stick to a language just because you've already studied it for a couple of years in high school. Of course, if you have achieved a level of fluency in it, you might want to polish it, but you might also consider starting a third language!
What sorts of careers are out there? Non-profit, charitable organizations, communication and journalism, international business (think of being bilingual and getting an MBA or information management degree). Then there is the State Department or law enforcement. Think of your dream job, then work backwards to map out what you need in terms of degrees and experience in order to make it happen.
Take language tests -- take the ACTFL's OPI before you make any claims to "fluency" -- it will provide you with a nationally recognized score that you can then confidently place on your resumé.