I have to say that it is far easier than I thought it would be. Given a few hours of effort and some good instructions, I've managed to turn myself from someone who doesn't have the talent for it, to someone who does. Or in other words, it is a learnable skill. I had art lessons at school and got nowhere. I pick up a book for a few bucks and I've made significant progress.
I think the secret is small steady progress. It gives your brain the time to absorb the teachings and knit a bunch of neurons together. They've done studies where if you play a video game, after sleep the following day, you are a little bit better. i.e. your brain has encoded the information a little better.