I've gotten many emails since beginning to share how I incorporate painting and scrapping .. and I try and tell everyone that it isn't just with a paintbrush that you can incorporate art in your layouts.
Start small .. something as simple as a white gel pen. Take an existing layout and a white gel pen, and just add outlines to the paper .. maybe the letters to make them stand out a little bit more.
Keep doodling ... use some of that blank cardstock in your stash .. and begin to make your own lettering, doodle flowers and build your layout around your larger doodles.
When you get comfortable with your doodles ... then just take a a couple of more baby steps and add color to your doodles with watercolors.
There are so many forms of art that you can use to add special touches to your layouts ... it isn't always with a paintbrush ... but it's always using your imagination.
So have FUN with it ... bet you create something wonderful!