When installing an overlap liner in an above ground pool sometimes you are left with a lot of excess liner to deal with. Most people tend to pull the liner straight over the sidewall leaving the excess on the outside of the pool.
This vinyl liner overhang on the outside of the pool can be cut off once the pool is full. It is best to leave at least two inches hanging over just in case the pool looses some water and the liner shrinks a little.
If you do decide to cut the excess liner just remember to never drain the pool. Draining an above ground pool is something that is seldom necessary except at liner changing time. Holes in the vinyl can be patched underwater and unsanitary water can be treated with chemicals.
The overall look of the pool is a lot better with a nice even overhang on the outside. Be sure to not make it to small. If you do not allow enough overhang the liner will tend to pull out.
If you have questions pertaining to above ground swimming pools feel free to ask the pool pro. The pro would be me and I would be happy to answer your questions.