Undergraduate / "car accident" Essay for applying at UCF as a transfer [4]

"car accident scene" - My first college essay!

Help!! I'm writing my first college essay and i am freaking out. I chose a descriptive topic, a car accident scene. I have my thesis statement but I'm having a hard time figuring out whats next and how to arrange everything. Its laid out as topic sentence of first paragraph: then it has A: supporting idea 1, etc and i have to have 3. Then concluding sentence. and thats on the instruction sheet 3 times.