#1 on your list to run the ramrod down the barrel to see if it is loaded, a pawn shop owner told me that over 30% of the B/P guns he got in were loaded. Pinch the ramrod at the muzzle when it bottoms out and lay it on top of the barrel to see if it extends just past the drum where the nipple fits. If the ramrod shows it only went an inch or more ahead of the drum your gun is loaded.
There is a lot more to checking a rifle to see if it can be fired, on many of the guns they weren't cleaned properly and the barrel may be rusted out, shine a light down the barrel and see if it is nice and shiny.
Most of us lube patches with something other than spit for patch lube although it works just fine for people who like it. I use Hoppes black powder lube and solvent if I am shooting of the bench for a long time, swabbing the bore between shots is not necessary with this stuff. I use mink oil for deer hunting where I may leave my gun loaded for weeks or months at a time.
Go over to youtube and watch a few M/L loading and cleaning videos, this is much better than us trying to tell you what to do when you have minimal experience, seeing it done is much better than us telling you.