I have made a lot of patches in 30 years of muzzleloading. The easiest way so far to cut them is with a hole saw with the drill bit removed and the teeth ground off with a bevel angling in from the outside.

I wrap the patch around a thin scrap board six or eight times and staple it down one edge to hold it, them put my cutter in the drill press and go to cuttin. Makes a lot of patches very quickly. Also, old sheets can be made into cleaning patches very quickly indeed.

I lube with saliva for the range, and bore butter for hunting (it doesn't get very cold here). I have also used neatsfoot oil as well.

Just keep the petroleum based oils out of the bore.