Staple a piece of pipe cleaner to the back of the frame to use as a hanger.
Hot glue the balls to the wooden frame starting at the top on the other side of the hanger.
Continue to glue the wooden balls next to the top one on each side.
Fill the bottom empty space with various faux artificial flowers and leaves.
Notes
If you can't find a flat wreath base you could use a large embroidery hoop.You could also add a ribbon or bow to the wreath. However, I think it looks great with just the flowers.Note: Originally I hot glued the pipe cleaner to the back for a hanger but after a while, it broke. So I used a heavy-duty stapler to attach it and now it's fine.