If you are considering an application for a grant through the Fulbright US Student program, there are some things you should be aware of and things you can do now.
Become familiar with the options available through the Fulbright US Student Program. The Fulbright website provides a wealth of information; keep in mind that WUSTL's deadline is a lot sooner than the national deadline.
The Fulbright US Student Program funds projects from all academic fields, including STEM fields and Creative and Performing Arts.
There is no GPA cutoff for Fulbright but applicants with strong records are likely to be more competitive. The level of selectivity depend very much upon the country to which you are applying and the number of other applicants in your competition year.
Three recommendations are required. Cultivate faculty who will be able to write a strong letter when the time comes.