It’s important that the dominant partner knows how to use a whip properly, because improper use of a whip could result in deep lacerations. In sexual play where pain is involved, complete respect - as well as a safe word - are essential.
A whip is operated in a swift motion where the flexible end slaps the receiving partner, often creating a sharp pain, and sometimes even mild cuts or scars, on the skin.
More About Whip
There are many different kinds of whips used during sex. A flogger is the best kind of whip for a person new to sadomasochism. An experienced dominant might go for a more painful and advanced type of whip, such as a single-tailed whip or a "cat o’ nine tails" whip. It’s also not uncommon to use a belt as a whip.