Make sure you tape the sides and hold down the paper when you are paining- that way paint will have less of a chance spilling out.
If you make a mistake, like I did, then you can fix it by using the same wall paint to do any touch ups. Tip: use a fine brush.
This project cost us literally no money since we had the supplies and paint. It took me about an hour and half. Creating your own stencil is perfect for a small area. However, I wouldn't try this same method on a large wall unless I was doing one color. I really like how it turned out and feel inspired to do something like this again for a future space- maybe our laundry room.