Hello everyone! :)
In a few days I will get to play Fallout 4 for the first time (late to the party, I know). I have a lot of experience from FO3 and New Vegas but I wanted to ask how should I play it for the first time. The classic way of just completing quests and levelling up as much as possible or should I play with a build?
I'd agree with Chunk. I started blind and then quickly got into building characters. I just finally finished the main quest and it was tough with all my "baggage" from being through many parts of the game before and honestly it was hard to finish..lol. So go with the flow the first time, enjoy the game. Then you can get into building because you won't want to go all the way to 40 or 60 or (heaven forbid) 90+ after you've done it a dozen times already..lol.
For sure approach general exploration pretty blindly (don't hesitate to veer off from the main quest, running around is way more fun) but for perks and SPECIAL you should consider doing a more "jack of all trades" approach so you can be open to using anything you find and figure out if there's a certain playstyle you end up liking. I'd always go for the cliche stealth sniper but when I did the jack of all trades playthrough I found myself really liking heavy weapons, surprisingly. Check out the perk chart (should be plenty online) and see what Special you need for some key perks like Life Giver and Medic. Have an atomic blast on your first playthrough :)