Induction and balloon?!

Amy • I'm 28 and married. Trying to conceive for 8 years and have PCOS. My baby girl is due December 18th!
I'm 38w6d and on Tuesday when I'm 39w4d I'm going to be given the balloon if I don't go into labor by then. I only just recently heard about this balloon thing, what should I expect? From what my doctor said I will get the balloon and then the following day I will get induced. I'm getting really nervous...