You only get 500 characters to describe each experience, so I used kind of a combination of paragraph and bullet point forms, much like you would on a resume. Example from my applicaton:
"As an Entomolgy RA, I studied insect pests of corn. Duties included design and maintenance of experimental plots, daily data collection and interpretation, and insect identification and dissection. I spent the summer working throughout the state, and getting to know the farmers on whose land our research plots were located. I learned about a lifestyle (farming) and fields of biology (agriculture and entomology) about which I had been wholly unfamiliar. For that reason alone it was a satisfying experience."
You need to be quick and to the point. Just say what you did, what your duties were, and what you got out of the experience. Hope this helps!
