pull

There are many, many ways to sign this concept. It all depends on what you mean.
In general you mime the act of pulling whatever is being "pulled."

PULL: This is the general sign. It could be used for "pull on a rope" but I've also seen this version used to mean "pull" a person or group to your way of thinking.

PULL: As in "Pull a tooth"

If you mean "pull" as in "influence" then you would use the sign for "influence." Example, "He influenced their decision."