Step 1:
I used green one dollar notes for the leafs, other green banknotes are fine too.
Fold the white edges backwards.

Step 6:
Fold in half.

Step 5:
Fold over these two lines.

Step 2:
Fold over these two lines and turn the model.

Step 4:
Press the model flat again.

Step 3:
Fold over these two lines. The corners indicated by the arrows are pulled upwards by making the folds.

Step 10:
Fold three standard printer / copy papers together in half.

Step 8:
Fold the stem in half, except the tip. Then curve the stem, see arrows as example.

Step 9:
Make 20 to 25 leafs

Step 7:
Make zig zag folds over the 4 lines, do the same on the other side.

Step 16:
This is one standard printer / copy paper folded in half. Roll up, use tape or glue.

Step 15:
One of three branches is done

Step 12:
Make a few zig zag folds on a large brown paper, the edges are used for holding the leafs.

Step 11:
Roll up, use tape or glue.

Step 14:
Bend / twist / curve the stem into the right shape, see the picture of step 15.

Step 13:
Wrap the brown paper around the white base.

Step 21:
Here, I'm glueing the two large branches together.

Step 19:
The third branche also has a base of three white papers rolled op together.

Step 20:
Glue the three branches together

Step 18:
Bend / twist / curve into the right shape, see arrow.

Step 17:
Make another brown paper with a few zig zag folds and wrap it around the white base.

Step 22:
And now the small branche is glued to the model.

Step 23:
The base of the tree is done.....