For bluing things I use PermaBlue, my old man gets them out at work in bulk tubes. It's stupid simple you heat up the metal (you can use a hair drier) you heat it till it's pretty warm to the touch, get you some of it on a brush or what ever your gonna use (I recommend something with a handle so you don't burn yourself, and you just repeat it till you get the desired finish. I used it on my mosin is several places, the bolt, the muzzle crown, and the where the bayonet rubs on the barrel.
As for other parts of the rifle if you have sticky bolt syndrome go to Iraqvetran8888 channel on youtube and he has a whole thing about that that usually works. I bought a polishing kit for my dremal tool and polished a few different area's on the rifle like most of the trigger and some areas on outer receiver where the bolt rubs.
Really theirs a bunch of stuff that you can do, like said it's really up to you, your skill, and what the rifle can do.
"come on you sons of b***hs! do you want to live forever?" Sergeant Daniel Daly, USMC, Belleau Wood France June 6th 1918
"You can be as mad as a mad dog at the way things went. You could swear, curse the fates, but when it comes to the end, you have to let go" Benjamin Button