I have found on the rolls that I have gotten in this size that the brown kraft paper bag has a black light tight bag right inside it, almost like it is affixed to it. I don't open it other than in complete darkness. I reclose it by rolling the edge on itself and securing with thre or four fold back clips, the first two by feel, then the last 2 by amber safelight.
I try to wash my hands to dispell excess oil, and keep at least the paper 'catchcer' hand in a cotton glove.
I use a guilloting type paper cutter, with the stop set to whatever length I am cutting. I cut it to 12" square, or 12x14, and later cut down to 11x14, or 4-5x7, or 8 for 8x12, and later 8x10.
I also cut it 16" for full frame 35mm aspect ratio enlargements (though not always with 35mm negatives). I have a roller processor that swallows anythin less than 12" wide, but I don't try to feed it anything longer than 16"
I feed the roll from the right, across the bed, and then move the cut piece into a partially open light tight drawer. Everything is by feel. I know you can use a very dim green light, but I don't.
Tidy the area first, and have a good mental and touch sense of where everything you need for the whole operation is before you open the bag.
You will likely want a vaccuum easel before long with this stuff, unless you like using and the look of a 4 bladed easel. The curl near the middle of the roll is wicked, and never seems to want to go away for me despite many efforts.