What should I wear at the dance?

So this coming Tuesday all 10TH graders are going to have dinner at school for our graduation and after that we are going dancing with all the schools in our community. I’m getting really stressed as the day gets closer… I haven’t chosen what I am going to wear. My skin is black by the way (African) what do you think would suit me? How should I have my hair, make up, shoes, dresses etc.
P.S I don’t want to over do it so have it simple please ;)
And yeah I have a lot of chicken pox scars on my skin. I got the chicken pox like 1 year ago. How can I hide them?