When he's learned all he can from the Pokéball, the Master will empty all his pockets out onto the bed.
After staring critically at the junk, he'll pluck out a paper birthday card that has been folded into quarters, a piece of already chewed gum put back in it's wrapper, and the rubber band from around a roll of alien currency.
When he unfolds and opens the birthday card, it begins playing a tinny birthday song on repeat.
It's your birthday, it's your birthday, it's your birthday. Yay! It's your birthday, it's your birthday, it's your birthday. Yay!
The Master rips open the card, cuts the string off the yoyo, pops the gum into his mouth, and gets to work.
A little while later he has a very shoddy but workable alarm on the door. If anyone opens it, the birthday song will begin to play.
After he's done, he'll shove his things back into his coat pockets mostly at random and go to sleep.