The first step is to make a list of:

• Every position of responsibility or job you have ever had, on or off-campus, paid or unpaid
• What you learned from each one in 5 words or less 
• What you did well to fulfill the responsibilities of the position

Next: Follow a standard resume format. Key elements of a basic resume:

• Your contact information (top of the page, centered)
• Optional: objective *or* key skills
• Experience (paid or unpaid work, campus activities, etc.)
• Education (in reverse chronological order)
• References with contact information

Remember:

• You are writing for a very specific audience - the person who will hire you
• Be succinct.
• Proofread, proofread, then have at least one other person proofread. There can be no errors on the page.
• Everything must fit on one page!
• Save as a PDF to avoid formatting or access issues for your reader.