13th Birthday Party

Okay well my 13th birthday party is coming up on august 18th and thats only 29 days ! theres nothing ready besides the candles for the cake. We havent sent out the invites yet or anything and dont know what to start . My mother passed last year so this is our first birthday party without her and she did almost everything for it . My dad has no idea what to do and keeps putting it off . Im about to cancel the whole thing because i have so much stress . Its a pool party with the theme of tiki/hawaiian stuff like that . Any ideas what to do ?