What are the steps (ALL the steps) to install TWRP + /e/ or Lineage + Magisk + MicroG on FP3+?

[LeVraiRoiDHyrule]

Thanks for your replies everyone !
I succeeded to clean flash LineageOS for MicroG on my FP3+, your answers helped me a lot. Thanks again.

But I’m having a concerning performance issue, I made a post about it here

Recently switched to LineageOS for Microg, performance in games is significantly lower and transitions are laggy

Hi, I have a Fairphone 3+, that was on its base FairphoneOS. I recently unlocked it and proceeded to clean flash LineageOS for MicroG. I also rooted it with Magisk. It is the latest Lineage 17.1, everything is up to date. But I notice that the general performances are much worse than with my previous base OS. For example, in the game “Mindustry”, I was running at around 55fps. Now, with LOS4MicroG, I am running at only 40fps. I observe the same behavious for most of the games, I nearly alway…

Would you mind taking a look at it ?

Thanks again for being an awesome community, have a great day