Making My Own Prom Dress: Part 1

So I've decided that it's time to begin working on my prom dress.  I need the dress to be done by March because that is when the Senior Fashion Show is at my school.  At the fashion show, all of the seniors wear their prom dresses and walk down the runway.  Today I went to Jo Ann's and got the materials and the pattern for my dress.  I'm going to use McCall's 5806 and make the white dress, but in green.

At Jo Ann's I purchased a sparkly emerald green satin.  I have yet to buy the chiffon because they did not have enough at the store.  Either I will order it online or go to another Jo Ann's to purchase it.  However, my next step will be to open the pattern and figure out if I need as much as they tell me.  My budget for the entire prom is $200.

Here are some celebrity dress that I'm using for inspiration:

Along with the dress, I'm hoping to make a matching purse and a tie for my date. I bought extra fabric just for those purposes.  I have a pattern for the purse, but I'm not quite sure yet how I'm going to make the tie.  I'm thinking that perhaps I can take apart and old tie and use that as a pattern, which (hopefully!) will not be that difficult.