Basically press and polish.
There are many ways to finish a wrap up to and including clear over it. Some products will make it slick. Some will make it grippy.
I have no idea how to finish a wrap and am using an original cortland wrap on my JOSS. I would cry if it needed replaced. Sure, you can still get cortland done, cuemakers have their stash and I know i could get a rewrap on an old classic like mine. But it has aged and would not be the same.
Find a wrap finished as you like. Send your cue to the maker who did that one. Just a thought.
I highly doubt it needs re-wrapped unless there is something not right about the linen.
How do you make a non-pressed Irish linen grip better?
No idea. Non-pressed? Without pressing it's kind of pretty rough. I really don't like it that way.
I have been down this road with my own cues (yes, even my JOSS many years ago). I tried so many different things. Waxes, sealers, polishing with fine grit papers, all kinds of things. I usually ended up with what I wanted. But it is simply so much easier to have a repair guy or cue maker do it.
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