Re: Drying of handmade watercolour paper
I'm not so precise generally, so I've kept my edges by casual taping in corners, etc., therefore haven't done this -- but faced with your problem I'd try:
Get a good quality two sided tape (expensive, the last roll I bought was $10 at NY Central, but extemely handy generally), and put it a wee bit inside the edges to fasten paper to whatever you're fastening to.
When print is done, use solvent to remove the tape -- I find TALAS "Undu" (or maybe that's "Undo") wonderful, for a million things. Leaves no mark, no odor, etc. Or just leave the tape... it's supposedly maybe really is
There's also drymounting & removal, if you can deal with it... some folks (Keith Taylor for one) do that, though his prints are only perfect.