I'm going to upload a simple demo to show how you can paint leaves and make them seem to be growing out towards you in a 3D effect. To do this we use a technique called NEGATIVE PAINTING.
Pity nobody can think of a better term, or a more positive sounding term! I've tried but haven't come up with anything yet! But it simply means that we are painting not the actual shapes but the spaces BETWEEN the shapes. By going darker in the negative spaces in between, we allow the positive shapes to jump out in a 3D effect. Magic!
Here's what you will end up with..I'll show you how next time. Give you time to do the drawing perhaps!