My personal favorite tool is a cone made of rolled plastic, similar to a cake decorating tube, with a tiny hole at the end. The benefit of such an application tool is that you can achieve incredibly fine lines. Usually, one cone can be used to decorate up to ten less-elaborately designed hands; for very detailed work a cone will cover two hands.
Using a mehndi cone is quite simple, though it takes time getting used to. A cone can be held in several different ways – like a cake-decorating tube, or like a pencil. I prefer holding cones using a pencil-holding technique because it allows me optimal control over line creation. In my method, I place the cone in my hand between my thumb and forefinger and curl my remaining fingers in for support. just try holding the cone like you would a pencil, apply more pressure as you are applying and modify the cone so you can allow henna paste to come out of it. Let the creation begin!