As a painting major in art school I never quite felt like I got a handle on watercolors, working instead in oil or acrylic. Recently I was testing ideas for a handmade Valentines story and made some super simple watercolor cards and had a tiny breakthrough.
Anyone could make these cards, simple painted hearts or stripes, but I finally practiced something that I remember a teacher telling me (and didn't listen to at the time). Let the watercolor do what it wants to do: pool up in some parts and remain dry brush-y (as the paint runs out off your brush) in others. I had always overworked the paint, layering it and covering up the pretty brushi-ness until it didn't glow as watercolors should. Simple as they are, I really like these Valentines!
A flat brush such as the one pictured is perfect for making the heart outline. I started in the center and worked my way up, around, and down to the point and then repeated for the other side. You don't need to follow that, after making a few you'll find you're technique! (By the way, you can't see it but there is wax paper covering my marble table...I don't recommend painting directly on top of marble!)
It's really important to use watercolor paper. Regular art paper will curl and buckle.
I cut it up into postcards but alternatively you could buy watercolor postcards.
If you have an inkjet printer that allows you to run paper through straight (i.e. It doesn't curl around a roller--mine has an option to top-feed instead of taking from the tray on the bottom) you can print over your watercolor-ed cards. It helps to cut your cards down to a standard size like 4" x 6" and make sure to specify the special size and that you are using specialty paper in media. Paint the heart FIRST and allow it to dry completely before running it through the printer.
I hope you'll try making these Valentines. They're super fast and fun to make. Painting them is addictive, and any leftovers will make great thank you notes!
Have a great Valentines Day! x