Getting the right prompt for generating high quality images can be really hard. Generally speaking, the more detailed you are on your description, the better the output image can look like. But there are also some specific keywords that can improve a great deal the generated art.
Picture it Prompt Suggestions feature shows you keywords suggestions you can use to increase the quality of your image, by simply clicking on the suggestion pills as they appear. Check the video below to see how much difference those keywords can make when generating the image of an angel for example: