2. Realise You Can Scrap Almost Everything In Sight
No, by that I don't mean throw all your unused goods into the nearest garbage can (not that they seem to exist in Fallout anyway). I mean that instead of selling any items that you don't see yourself ever using, break them down into scrap instead, because you'll be able to use this material for weapons and armour mods, as well as settlement-building. Learning the basics of crafting in Fallout 4 really pays dividends, because breaking items down into scrap to make your own weaponry is a far more effective method of acquiring items than buying them for extortionate amounts of caps off traders. Even if you don't end up using all the scrap-crafted bits, you can sell off your creations to traders for solid rates. Of course, once it's scrap, there's no turning back, so make sure you definitely want to do it before committing.