You can draw inspiration from real-world locations and tweak them. Maybe combine the names of two existing places or use elements of nature and mythology. It's all about creativity!
I'd say start by imagining the unique features of the place. Like if it has a special type of landscape or a unique culture. Then look for words related to those aspects. Or, try using puns or alliteration to make the name more memorable.
Well, one way is to think about the theme or mood of the fictional place. Is it magical, mysterious, or peaceful? Then look for words that convey that. You could also combine words from different languages or make up completely new words that sound cool and fit the place's character.