My first time using watercolors was actually with my altered book. Before you get anxious about using a new media or thinking you have to go out and spend a lot of money, you should know that I use children’s Craylola watercolor. You can find it at any Walmart for fairly cheap.
The thing to keep in mind when using watercolor is to be patient. Give it time to dry before you start layering it because if you don’t, it will smear and blend together. Sometimes this is still beautiful, and sometimes it just turns brown, but even if this happens to you, don’t worry! You can cover it up with a cut-out from a magazine or let it dry, and paint or write a quote on top. It’s not a big deal.