I submitted a cover letter and filled out an online application that discussed my skills and past experience in the field, as well as willingness to work on certain projects. I also had to give contact information for references. After a few days I was contacted by the people running one of the projects in which I had expressed interest. I was asked to send in a number of writing samples. I was also asked to commit to a video conference interview. The interview was casual; I got the sense that the two interviewers just wanted to get a feel for my interest in the field, as well as my experience, while also gauging whether or not I'd be easy to work with over the summer.