Colors have always been a sure way to unwind. Work on the garden sketches and use colors as per your taste. Maybe you could give ideas to the creator himself. Work on the couple of pictures with umpteen options and take printouts ..
Click on one of the pencils on the screen left and drag it to the sketch. Selected areas get highlighted which is understood to absorb the pencil color that you use at one point. Replay for fresh work and click done, if you have finished.