Here is the 4th cover for the friendship series called "Picture Perfect" I've been illustrating for HarperCollins. Attached is also the sketch that was chosen for this. I ususally turn in about 3 to 4 different sketch options when I'm working on a book cover.
I really try to keep the look and feel of the sketch alive when I go to color in Photoshop.
This series if full of lots of fun friendship drama.