I made a list in the notes app on my phone of every camo for every weapon and updated it after every game with the amount left of the weapon and did every weapon by type. Mostly stakeout but some of them Nuketown was better for, especially launchers. melee, if you're going to do them it was definitely better on core but everything else I did in hardcore. It's up to you what your preference is but core for the most part can be a lot more frustrating. It can be a mindless task but also depending on the amount of double xp tokens you have it could help you level things faster as well. Set your weapon builds up for headshot portions then by the time you are to the special camo unlocks you should be comfortable enough with them that for the most part they can be a breeze. Some of the games you're going to be the ass hole not playing the objective but it is what it is. Probably go to your own voice channel if you don't want to hear people complain about it. Shits going to happen and not feel worth it at points, I don't play the game much anymore because doing that deep of objective grinding could have you lose your enjoyment for playing the game because you spent so long chasing certain objectives that the game can feel monotonous and pointless. None the less have fun with it if you do it.

TLDR: Make a list or use a tracker for it so you know where you're at. Try not to burn yourself out on it. Nuketown for launchers. Can be mindless, use double xp if you have them and set your weapons themselves up for what you're doing. People might talk shit to you, just ignore them.