Just my take on it... other opinions are also available.
Don't worry too much about the handle/arrow shelf etc until you have the limbs bending smoothly.
It's all about the tillering, you don't make a bow and then stick it on the tiller.
You rough it out, tiller it, then finish it.
The advantage of this is you do the important bit first and hopefully get a smooth working bow.
IF you then cut the grip and shelf all wrong and it breaks at the grip you have at least learned how to tiller it. You've also learned how much you dare cut out for the arrow pass.
It also gives you room to make the grip and arrow pass match up to the string line if there are minor adjustments needed.
Don't get suckered into finishing it before it's done.
Del
(I don't go out and sew a leather grip onto a tree, and then fell it
)