I have noticed one thing- meows work!
And if you are consistent with your meows, they work like magic!
Like if I want the human to play with me the meow I make is ‘meowwwwwwww’, or if I want cuddles the meows I make are sort of like ‘meeeeeeeow’. Be consistent, do it a couple of times and the humans start to ‘get’ it.
Try it, and tell me how you go- okay?
Sometimes the humans need some basic training, but I have to say they do make good pets!