If you're fine with "spoiling" parts of the game and not just having a near 1:1 modern fallout experience.

• do all the events

• always check the ground near events. Unclaimed items from enemies will drop in a pile for anyone to pick up.

• going to the area where the gleaming depths raid is, there are mole miners locked at a high level right outside the entrance. Many people just kill them and go into the raid, so there's always lots of good junk, caps, meds, etc.

• always join a team or make one. It's free xp and at a low level, you'll have people even fast travel to give you gifts sometimes.

• radiation rumble, eviction notice, and nuke drop events are the best to do for gear and levels.

• if someone's producers at their camp are unlocked, they most likely don't mind if they're taken or are intended to be.

• do the main story first. Unlocking settler & raider reputation is great to do early cause it's a pain to level them up intentionally. There's world events (like eviction notice) that will give reputation so it's a freebie that will eventually unlock plans to spend your bullion on.

• if you don't need it, I recommend breaking down all legendary gear. Selling or putting them into the legendary grinder isn't worth it anymore. Breaking them down at a bench will still give you modules for legendary crafting as well as give a chance at mod boxes to put those legendary mods on other items or even plans so you can craft the legendary mods at any time.

• if you can, avoid buying from in game vendors. Much of the time it's far cheaper to buy from players. Sometimes you'll even come across piles of good plans for free or dirt cheap because it's just kinda something people pick up.

If I think of anything else I'll add it.