Cthulhu is a bit complicated. You need deep sea aquatic components, maybe fuck a fish, live in an isolated fishing community, stuff like that.
Each demon/devil has its own ritual, so you'll have to look them up by name.
For the gods, you need to commit some sacrilege if you want a quick and dirty response.
For the fairy godmother you need to be poor, orphan, have evil step family that doesn't get stuck in washing machines and only own rags.
For the Oz trip, you need to wear a pair of ruby shoes, get high, spin around three times and click your heels while fervently chanting "There's no place like home." Obviously it only works when you're not home.
For the monster under your bed, the main thing is thst you need to sleep on your bed with a limb or body part of choice sticking out or touching ground. After that, it depends on your monster mostly. Each one has its own preferences. Some like it when you're clean, others only want dirty or stinky body parts. Some drag you under the bed and eat you whole, others just kill you because you annoy them. It's all very individualistic.
For the rest there are many guides online, I'm not going to bother explaining them.