It is known that sleeping humans are boring. The "direct approach" is nearly always successful in rejuvenating a dormant human. Do one of the following:
Trample, purr, meow or head-butt.
If the human is being stubborn, you may have to resort to more drastic tactics, such as ripping down posters, rattling blinds, or singing at the top of your voice. Eventually the human will get up and do what you want, usually in a disgruntle manner.