Well, in the colder months I've just spread the leaves out on some newspaper and left them in the spare room to dry, just turning them over once or twice a day, the central heating seems to do the trick in a day or two, brambles are really quick to dry, but I find plantain can take a week!
Some people pop them in an airing cupboard, or in a very low oven for a short time, I think you have to keep a close eye on them in the oven.
On a warm day I've just spread them on newspaper on the garden table with a bit of mesh on top to stop them blowing away.
You'll know when there ready to store when they go crispy, if there not dry enough they may go mouldy in storage. I just mix all mine up in a cardboard box to store. I don't think it's recommended to store in plastic bags.
Try bramble leaves first, they are really easy, and don't shrink down to nothing like some leaves do. It never ceases to amaze me how huge a pile of forage shrinks down to a small handful of dried forage.
The buns love it in the winter months though, so it's worth the effort :thumb: