I have this 12k Chinese stone. I want to use it for touch ups, which method should I use?. and should I apply pressure?. I just don't want to ruin my razor. but also I want it to keep that sharp edge.
In addition to Slash's recommendations, if you're going to use the C12K for a refresh some type of slurry is going to have be involved. If you have a Tomonagura or something to help you create slurry that won't scratch your C12K too much, get a lite slurry going and dilute getting to water only.
You don't need slurry if you have plenty of time. 100 laps with just water should refresh the edge. No pressure.
Simply soak the stone for a few minutes and keep some water on it, and hone, with very light pressure, basically just the weight of the razor and half a finger. Normal, alternating laps, with a slight x stroke. A more full X stroke of course, if the stone is not wide enough to carry the whole edge.
A good test, both before and after, is to pass the razor 1/4" over your forearm and notice whether it treetops any hairs, how many, and how much it catches or how loudly it pings. When you see a noticeable improvement, you are done. Almost. I like to use a half dozen laps with the spine leading, then a couple just pulling the blade across the stone for a finish to the finish. That last movement is tricky because you don't want to "bend" the razor over the edge of the stone. Best results all around is from holding the rock loosely in the off hand so it floats in space, and let the razor and hone find their own alignment. If you lay the stone down on an immovable surface, you are very likely, as a beginner especially, to mess up.
BTW, lapping film is better.
BTBTW, balsa, lapped flat and smooth, with .1u diamond paste on one side and .5u on the other, beats the pants off any honing method for edge maintenance. Just strop 4 dozen laps on the fine side after each shave. If it ever does seem to be getting slightly dull, visit the .5u side with as many laps as it takes to bring it back, then continue on the .1u side. Magic. I never have to re-hone.
What does your razor look like? If it's a smiling razor, you will need to do a rolling stroke so the whole edge gets hit. I usually don't do ALL alternating laps, rather I do a bunch on one side (maybe 50 for a CNat), then flip and do the other side, flip and do half the original, flip, etc. For my CNat I would do 50, 25, 15, 10, 5, 3, 2, and then do 20 or so alternating strokes to make sure things are even. I don't worry about using a bit of light pressure when doing the larger sessions, but try to ease up and get less and less pressure toward the end. It's worked really well for me. That CNat should keep you going indefinitely, unless you are like me and wind up with a bunch of hones... My CNat is a good stone, it leaves a very sharp edge, but not buttery smooth. The edges get very close with the grain, so it doesn't matter so much to me, but I can't do ATG under my chin with the CNat.
i like the cnat it is slower but teaches good strokes and gives very good edges IMO a perfect maintenance hone. and a slurry stone for it is not necessary IMO for maintaining a shave ready straight. i like cnat edges by the way but all natural stones are not alike.
I put oil on mine.
If you like it, put a rang on it.
Open a door. Use C12K as a door stop. Order new hone. That will be faster.
Open a door. Use C12K as a door stop. Order new hone. That will be faster.