I'm just starting to look at things and get ideas for my wedding and I decided to messure myself to see what size of dress I would be but I know I want to lose weight before my big day. How long should I wait to buy my dress so I lose the weight I want but not be in a hurry to buy it before the wedding?
It really depends a lot on where you're planning on getting your gown. If you're ordering a gown that needs to be made it could take up to 6 months... then you need to add in the time for alterations (and troubleshooting, if there's an issue). If you're planning on going off the rack, you can wait until 2 months before your big day.
Just always keep in mind, time for alterations... time for issues to arise, and get solved... etc.
It's difficult, for some brides, to plan a wedding without a dress (harder to pick out BM dresses, colors, FG dresses etc.)