First thing to do, it to find out what part of the stave to use. Which side will be the back of the bow? Which side will therefore be chopped away? That side should contain the most knots. Also, determine what length the bow will be and what length the stave is. It's not uncommon to closely inspect the stave (sapling) for at least 15 minutes before you do anything with it. Mark any knots, sideways bend and reflex or deflex. Determine where in this particular piece of wood the bow is hiding. Avoid the big knots by chopping them away as much as possible. If you're still left with knots, place them in the center of the bow's width rather than on the edge.
Once you determined where the bow is laying in the wood, cut off the excess length. Mark the centre (will be centre of the handle) and the handle itself (a few inches up and down from centre). Mark the back half of the bow and draw a centerline across the entire length of the bow, in the middle of the back. Mark the belly half of the bow-to-be. This needs to be the half of the sapling that you going to chop away.
Then start chopping (axe, hatchet, bandsaw, drawknife, big kitchenknife, whateva). Leave then handle intact (completely round still) and start from the fades out towards the tips. Cut all the way down to the pith (centre) of the tree. Effectively create a half round log, where the handle is still fully round. So you're making something that resembles
this bow, except that your width profile will be different. Note the full-round (bark still on) handle, and pith running on the upper limb. You can narrow the tips a bit already, but make sure to leave the bow wider than your final dimensions. So taper it from full width at the handle fades, to maybe 1" wide at the tips. Then remove the bark CAREFULLY: you must not damage the underlying wood. Seal the ends. In my opinion, it's not necessary to seal the back as well. Put to dry horizontally for about two weeks. Not in an overly dry room right next to heater, but just in your bedroom for instance.
After a few weeks, the wood has lost a considerable amount of moisture but will not be completely dry. However, it is dry enough to start refining the design and start tillering up to floor tiller. Press the handle of the bow with one hand, while your other hand supports the upper tip. The lower tip is pressed against the floor. Apply about 30# of pressure. Remove enough bulk from the stave until the bow will flex a few inches with this 30# applied during floor tillering. When the bow is floor tillered up to this point, put it aside to dry for at least another week. Then continue tillering and shaping the bow.
