Know Where to Find Help With Crafting, Quests, Etc
If you're new to the Fallout series or open-world RPGs in general, or you just think that you might need some assistance, you'll want to gather a list of resources before you start playing.
To level your character, you'll need to perform quests. To enhance your guns and armor, you'll need to craft. If you don't have a lot of time to play, you might want some help. Fortunately for you, there will be a lot of help out there.
You could pay for a strategy guide but you don't need to do that. Two places in particular come to mind right now. The Fallout 4 Wiki is a great place to start if you're stuck on a quest or don't know where to find a material. We also enjoy the guides on GameFAQs.
We should see a ton of resources pop up after the game is released so you'll want to hunt around for your favorite.