Make sure you meet the internship requirements. You must be pursuing a degree actively at an accredited college, able to demonstrate impressive academic achievement, able to work legally in the U.S. and be on track to graduate within the four-year-period Adobe considers for current applicants.
Register with Adobe online (see Resources below0. Look at the available internship positions to see which match your skills set and career preferences. You can even enter a profile to help match you with the right internship.
Submit a resume in PDF format. Identify the specific internship you are seeking and how it fits into your career plans. Include job experience and a short paragraph describing your personal interests outside your career. Don't use fancy type; 12-point Times will look far more professional.
Attend an Adobe campus recruiting event if at all possible. You will get to meet Adobe recruiters and ask questions about ways to improve your selection chances. This is an excellent opportunity to make the personal contacts that give you the edge in the selection process.