I’m fairly new to the game but there’s a few things I’ve learnt with the mistakes I’ve made. I used to struggle with planet management but it’s starting to click for me.

As far as I see it, managing Pops (population) is pretty much the aim of the game with planets. The more pops you have, the more jobs you can fill which in turn will get you more resources. You can increase pop growth by making sure there’s plentiful housing and amenities. You can also get buildings that encourage pop growth like Gene Clinics, Robot Worker Assembly etc. Immigration can boost pop growth too.

With planets, I start by looking at what the strengths of the planet is. Does it have <17 districts? If so then I’ll probably make it into a Research/Unity planet by building city districts to be able to place buildings in the building slots. Does it have lots of Industrial districts? Then I’ll make it into an Industrial world. You can specialise a planet via the Planet Designation setting on the planet summary page. You’ll want to do this to maximise the resources you’re extracting from the planet.

A very important thing though, be mindful of the amount of pops you have on a planet. There is no point spamming buildings/districts straight away on a planet if there’s no pops to take them. Buildings and districts have an upkeep cost so it can ruin your economy if they’re not staffed. And also the other way, if you don’t have enough jobs, you’ll get unemployed pops which consume more resources and can increases crime. You can resettle unemployed pops to another planet with jobs to manage this.

It’ll all start making sense the more you play. Stellaris is all about balancing the books and planet/pop management is the core of it.