Do you start with the terrain, the roads that connect things together, sketches, or what? I'm lacking inspiration completely.

I need to make a few different environments, desert, forest, plains, and ice.

I started with this for paths in a desert city top down view but dunno...

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Another thought is just a linear town in a canyon.

What do you guys do to get inspired? One of my holdups is that it's going to be for kids so I need to keep it simple but well done.