I painted two trees on my daughter's wall - my artistic brothers would be proud of my work. I drew them all by myself. And I'm quite proud of them. To make the flowers, I used a circle template and cut 2 sizes of circles out of pink craft foam. I double layered the flowers, so I half the flowers have a dark pink base and a light pink top, and the other half are light pink on the bottom and dark pink on the top. To attach them to the wall, I used pearl head straight pins. I didn't want to glue them to the wall since I want to be able to remove them some day. So I just pushed them through the foam and into the wall. Easy peasy!
Here's a close up of one of the flowers.