IF your 12K is one of these:
Attachment 260087
That's a Guangxi/Chinese 12K stone. It usually comes with a rubbing stone made of the same material. The stone is pretty slow, very fine, and very hard, but also most of what you need. There are a few ways to go about honing with just that and maybe a handful of inexpensive rubbing stones to help polish the edge.
Edit - I see that's exactly what you've got. The route I typically use one-stone honing with this fellow is to set the bevel, your sand paper should work for that. Then I'll use a piece of coticule, doesn't have to be big, to make a slurry on top of the stone. I do a few dilutions, until I'm almost on pure water. Then I switch over to the rubbing stone that came with my Guangxi and make a medium slurry with that. I'll dilute that mix until I'm almost honing on pure water, then wash the stone and do a good number of passes on pure water.