Some applications require resumes , transcripts, references, and cover letters but most are no more difficult to complete than any other job application. First year students and students who are not US citizens should apply to 15 or more internships to be sure of getting one. Use your contacts, those of other students and those of MHC faculty to find internships. Remember, faculty members of every college and university and medical school as well as staff members of companies who are looking for summer interns are eager to talk to you. Call a professor and ask her if she is looking for an intern.
Web pages are gold mines of information on the programs.
Most professional organizations have listings of internship opportunities. Your department office also has postings of internships. The NSF's Web site explains the REU Program and has application information and links to lists of all REU sites around the country. NIH has similar information on its student training Web site. Howard Hughes Medical Institute HHMI has information on many disciplines.