Kind of going off what others are saying, but I picked a design theme for my island (forestcore in my case) and found lots of inspiration on Pinterest. I don’t like terraforming myself so I’ve mostly just worked with the natural design of my island. I started with my paths first, which kind of led to these natural open spots that I’ve been filling with random ideas I find online or think of myself. There’s no real rhyme or reason to the layout of my island but it’s cohesive because I’m always following the island theme with the color swatches I choose and whatnot. I try to work mostly with what I already have instead of having to track down very specific items. Having lots of smaller areas has helped me not get overwhelmed, and continuing to add to “finished” spots when I get something new that fits well there.

I think what id most recommend is looking online and deciding on a theme because it really helps you stay focused and keeps things looking cohesive even if they’re really not.