>>2106865Professional Bowmaking is about making bows from fallen trees, it is no good for amateurs without specialized tools so ignore much of the written theoretical material altogether.
You need to find a straight tree branch without knots (that is small branches - this may be the hardest part of the project) with proper length and possibly even thickness of about 1.5 inch in the middle - then you taper gradually the thickness by reducing the side which was closer to the ground (called "compression wood") and taper linearly the bow's width to about half an inch at the ends. Ideally you should wait about a weak between stage one and two to give the wood a chance to dry - the bow will be much less gummy and will last longer in a good shape.