How do I cycle my new 20-gallon gl tank?

Okay, so I'm a beginner hobbyist who didn't understand that new aquariums needed to broken in with a process called the nitrogen cycle. I was misled by a pet store employee because he had told me all I needed was a Penguin filter, Prime Conditioner, and Tetra EasyBalance to get started and add fish after a day or two. I treated the 20-gallon tap water with Prime Conditioner and Tetra EasyBalance and installed the filter approximately 36 hours ago. I'm planning to get a much-needed submersible heater with 100 watts. Please tell me if there is a need for any other actions because I'm pretty sure I screwed something up. Additionally, it would be extremely helpful if you give me some accurate, expert advice of what to do next and how to cycle my new tank. Thank you!