I wanted a girl so bad but I'm having my 3rd boy.
Ok so i found a great poem online thar is totally me and used a pair of baby socks and a little blue beanie to announce it to all my friends..
We bought colored smoke bombs and took simple pics. It turned out great. We are having a girl.
We did I gender reveal cake, you tell the bakery what color ( in your case blue, ) icing to put into the middle, once you cut it open, gender in shown.