This trick involves the utmost silence & hones your stalking skills. Make sure your human either thinks you're somewhere else or has no idea you are anywhere around. A loud meow from another room will serve this purpose.

While your human is otherwise occupied, begin your stalk. Ideally, with female humans, a good place for them to be is in their litterbox room - in front of that shiny window they sometimes admire themselves in. If they are playing with the fur on their heads, making it curly with that hot skinny thing, they are usually too busy to notice you sneaking up behind them.

Just as your human is completely involved in their activity - scraping fur from their faces (male humans) or playing with their head fur (female humans) - gather your hind feet & leap up onto the human. Ideally, your leap should place you squarely in the middle of their butts. Immediately start your climb, taking care to extend your claws as far as they will go, to give you a good grip on both their clothes & the skin under. Make sure you stay in the middle, so your human can't reach you & stop the trick.

After you get to the top of their back, pick a shoulder & sit on it - digging in with your back claws, so you can't be quickly removed. Start surveying the scenery at this new height - make sure you look real proud of yourself & purr real loud. It'll help keep you from being punished & usually makes them laugh. When the human grabs you & makes you get down, look indignant & pout. It makes them feel guilty for getting mad. Wait a few days until they forget - then repeat.