Reference
I've made a few self bows, but not enough to get good at it. I would suggest getting a copy of Traditional Bowyers Bible, volume 1. Lots of info on there that would help.
Is your bow floor tillered? Usually, you start bending the bow with a string that is longer than the bow, and stress it a little at a time to see that the bend is even. Any spot that seems to be bending more than the rest of the bow is going to be where it likely breaks if it is going to. You have a good length, so that should help it. One other thing they stress is to never pull your bow more than the draw weight that you want. First bow, I'd go for #40, maybe 50 max. Not fun when you do a lot of work and tillering, just to have the thing blow on you. Good luck.