Inkscape and reading one article before I try drawing each picture. That way I actually get to learn Inkscape properly as I go along. I'm learning loads of stuff about vector drawing and really do recommend the program. And it's FREE! What's not free, is the book 25 Quick Cartoon Characters by Christopher Hart, but it is well worth the few pounds it costs, whether it's for you or the kids. I'm over 50 and finding it really useful!!!