The cover is usually made according to the requirements of the owner
Even many owners have already designed the cover
Look at other people's designs to understand the meaning of the work
Then go to find a few close to life, easy to understand the work to imitate
The purpose of imitation is to familiarize yourself with the use of current software
Then make a similar work to the imitated work according to your own ideas
Then make a similar work to the imitated work
Then make a similar work to the one that is being imitated. and then make something similar to the one you're imitating.