Questions to consider:
Written
Do you have a piece of writing, presented in any context, for which you are particularly proud? How would you compare your writing skills relative to your classmates? What kind of feedback have you gotten on your writing from experts like professors or editors?
Oral
Have you had the opportunity to present information orally to a group? How confident were you about your content? Your personal presentation, including body language and voice modulation? How was the material received?
Aural/Listening
How have you demonstrated the ability to take in information aurally? How confident were you that you understood the content and were able to explain it to others?
Visual
Have you had the opportunity to communicate an idea visually, such as through a creative work, illustrative data, or other images? How confident were you about your content? Your presentation? How was the material received?