A great thing is that it's like getting a temp tattoo. But like said in the previous post make sure that you go to a reputable henna design artist. Henna has a very distinctive smell and it does feel cooling to the body. So make sure you stay safe.
Drawing on hands to show the numbness and tingling sensation you get from smoking on hands and feet. Very complex design. Looks like the person is wearing gloves, could resemble how the smell of smoking clings to hands like a glove.