MAKE SURE THAT THE DEVICE THAT YOU ARE USING IS IN A STABLE POSITION SO IT WON'T SHAKE. Use your hands or really anything to launch the scratch cat into the air and around the screen. To pick up things, shake your hands (or what you're using to move the cat) slightly so that the code knows that there's something there.
I know that the projects that I'm making in Scratch 3.0 aren't as good as the ones I made in 2.0 (in my opinion), but I'm just getting used to the update. Enjoy!
