Start by having your toddler place three Popsicle sticks in the shape of a triangle. (We used colored sticks. If you don't have those, the kids could paint them.)
Use hot glue to hold the sticks in place. Then I placed hot glue dots around the tree and he put puff balls around the sticks. I cut a piece of ribbon and hot glued it together to make a circle. Then I hot-glued it to the back of the tree.
We cut a piece of brown foam and hot glued it to the bottom of the tree to finish it off.