Whenever you are ready to go. It was a good idea to wait a little while, but if you wait more than two more weeks to get started you are just procrastinating. The only reason I wait to edit anything is that I don't want the same wrong idea that I thought made sense when I wrote it still in my head--I want to read it without it taking me back to when I wrote it. Sometimes there is no way to wait long enough--that's why editors have jobs--the author may not always be able to do it himself. I think you've waited long enough that the beginning of the book (or whatever part you wrote first) can be read with a fresh outlook.