An effective internship application should include a brief introduction, even if a resume is attached, to personalize the submission. It's important to avoid simply reiterating resume content in a cover letter; instead, it should highlight unique qualities and motivations. Applicants should express their interest in the specific project and articulate how the experience aligns with their long-term goals. If applying to an unfamiliar organization, securing a reference is crucial, ideally from a tutor, to vouch for reliability and research potential. The application approach may vary depending on the type of internship sought.