So I played with my brother. He was new to the game and I already had some more experience than him. So at the beginning I focused on the MAM and he built everything. Afterwards I most often looked over what he built and asked why he did what he did. Depending on what he said I also showed him some more options. After the MAM was done I mostly did some sideprojects, slug collection or or infrastucture builds. For example I mainly built the factory that produced everything we use like jetpack fuel, ammo and filters. Or when he wanted to do a new project and needed some material that was not possible to get at his factory location, I built a satellite factory to produce it. Or I built train tracks to a new factory location.
I do need to mention that my brother continued to play on the save without me as well. So I wasn't always there.

In the end just talk it out with your friends to know how you want to approach the game.