Okay, so maybe “cheap” is an understatement. Start with a paper towel roll cardboard thingy and end with a paper plate. This is by no means a durable or reliable solution to hold your phone, but we’re trying to save money here.
If you’re just getting into making videos, your phone will likely be your only camera. Although I strongly recommend getting a cheap tripod, you may need something right now, and this will do the trick.