Thicker trunks with free-hanging ends
1
Start by cutting about 1/4 of the diameter of the trunk on the side you are standing. Lean slightly forwards and stand a bit to the side of the cut.
2
Now cut about 1/3 of the trunk diameter from the bottom.
3
Lean over the trunk and cut about 1/4 of the diameter from the opposite side.
4
Finally, saw the overcut from the top down until the trunk breaks or you reach the corresponding cut from the bottom.
Safety first! Pay close attention to how the trunk is reacting at all times.