I wait till the bow is shoot able before adding the tip overlays. First reason is sometimes I pike (cut off some) to reach weight.
After I add the overlays I shape and reduce the tips and last 6 inches of the limb tips. Narrower and,thicker is my goal.
The lighter the tips the less hand shock.
The scraper will be your number one tool. Caution, the easiest mistake to make is starting the,scraper in the same,spot too often. It is easy to have a,dished area that will turn into a hinge.
Dean Torges method is to draw a,line 1/8 inch in on the face of the limbs on all sides. Then another on the side edges. Then remove those four corners after this you,start on the flat,surfaces. Once wood is,removed so that most of this facet is removed you do it over again.
When using the scraper count your strokes and repeat on each limb. This will help to even things out.
A board with sandpaper or a flat disc palm sander in between scraping can help keep things flat.
Just to repeat, the easiest mistake is to get a thin area and this a hinge .