Do positional assessment evaluations and then make value judgements based off immediate priorities. For example, if you're about to be checkmated or can win a free piece without compensating the opponent then it would render their weak d6/d3 square or backward pawn on an open file irrelevant. You need a thought process:
1.Calculate the forcing moves first.
2.Activate your least active piece.
3.Plan around their most exploitable weaknesses.
4.Don't help them activate their pieces through exchanges.
5.It's better to attack than defend, but learning how to defend properly is still critical, since poor defensive technique loses the game whereas a failed attack is usually equal.
On the last point, someone had a successful attack against Petrosian, but his opponent didn't realize it and he withdrew the attack, and played f4 too late. So don't underestimate attacking chances if your opponent is seemingly well defended.
So i've recently started playing chess and consider myself quite average. 1200 elo and notice in my own games, I do tend to make blunders quite a bit. Some time ago, (maybe on a Youtube video?) I saw someone list off a sort of guideline that they use to make their moves. E.g. Does this weaken my position, does this set up my opponent for a potential attack, etc.. etc... I've started to try and be more aware of such possibilities but I'd appreciate if any people could share their own "guidelines" for their moves. I'd like to improve my game but I feel like it goes far beyond merely studying opening/endgame theory. Thanks in advance!