What sort of vibe is it? Details, man, details!!
One trick i quite like is (if it's a standard shape) laying it sort of...length ways..so that it runs from the top of the cunt to the bottom....do this and push down (hard) and..move one's hand at the same time...and mmmmmm. *grins and blushes slightly*. It is especially nice if you've already cum and are seeking a subsequent one.
sl