See how you use PS yourself. If you are just getting started, you can look for the basic course first. After reading it, you can practice how to use various tools by yourself, find examples for reference, and know how to use them by looking at more pictures and doing more. After you are familiar with PS, you can go online to search for a sign that PS is doing better and do the same thing with reference. By analogy, you can use your favorite characters and similar materials to make similar signatures.