Your theme’s name is important, and it shows up everywhere. It’s one of the few pieces of information, besides the theme image, that your user has when deciding whether or not to give your theme a try. Your theme’s name helps people find your theme, and distinguish it from other themes. And, your extension name becomes your product page URL on addons.mozilla.org.
To determine your keywords, think about what words a person searching for a theme like yours might type into a search field. For example, what words would someone use when searching for a summery theme?
Example names:Simple Space StarsSpring Garden TulipsBlack Pixel Fox