Choose a quote and write it in sharpie. You may want to write it in pencil first. Make sure you use sharpie so that the watercolors don't make it smudge.
Choose a color scheme and start adding colors to the white space. Don't be afraid to paint over the sharpie.
Continue to add splashes of color in random patterns. Feel free to play around with saturation, and vary the amount of blendedness for each new splotch of paint.
Now, start from a different corner and use somewhat contrasting colors. This will give your painting some variation. Don't let them bleed into the other corner just yet.
Then, start to connect the two corners with coordinating colors. This will blend the different color schemes and allow for a variety of colors to flow together in the same painting.
Continue blending the corners together and keep adding more color bursts along the way. As you go, branch out toward the other corners and fill in what is left of the white space.
Keep extending the colors toward the other corners until you have achieved a generally rectangular shape.
And now you're done!