First thing that came to mind was to ask you what type of wood it was. Then I smacked myself on the head and said, "That's a stupid question, John, duh! Doesn't matter what kind of wood it is, you just don't violate the growth rings, especially around knots."
I usually leave a raised bump overtop of a set of pin knots or whatever knot is on a limb. I do this by carefully chasing one good growth ring across the whole bow, taking extra time and effort around getting that knot's growth ring exposed. Sometimes I have to go so far as to use a set of tiny carving knives and dental picks to follow that growth ring around the knot. Then I draw a circle around the knot with a pencil and leave everything inside the circle while I go down to the NEXT ring. That way I have an extra cap of wood over the knot to hold down splinters, etc.
Now when you define the edges of the limbs, be sure to follow the grain of the wood. The grain lines are the lines that wood naturally splits along when a log is split out, like for firewood or for fencerails. The grain of the wood will probably flow out and around the knot just like a little creek will split and widen out around a rock in midstream. If you follow that grain like gospel and treat it right, the bow will remember this and reward you for it.
That's what most people mean when they say leave a little extra wood around a knot. Lastly, leave a little extra on the belly at that point, too. It should show as a bit of flattening in the curve of the limb when the bow is drawn, a flat spot. Yeah, you heard right, you don't want perfect tillering and perfect arcs on a limb with a knot.
Clear as mud?