First, take brown cardstock and cu out all four tree trunks as shown in the image.
Take the large tree trunk templates. The tree consists of two sections a top (with branches) and a bottom. Cut out both pieces. Glue the top onto the tab area of the bottom piece.
Place the edge of a ruler on the tree's middle line. With the ruler to guide the tool, score along the entire line. Do this for all the trees and fold each tree along the middle line.
Glue two trees together along one half side, aligning them along the edges. Similarly glue the two remaining trees together.
Glue both paper tree pairs together, aligning them along the edges. Now make enough leaves to cover your tree and finally, glue the leaves on the tree branches.