Taking information from Karen over here - (go down to her entry for 2nd October 2012), I decided to dry some of my herbs for winter. She recommends they are spread out on a sheet of paper towel and microwaved on full power for 5 minutes.
My rosemary appeared to not be very healthy this spring so I bought a new one. That promptly died except for one sprig which I used to test this way of preserving.
I allowed them to cool then crushed them with my fingers before packing into a clean herb jar. Not much, but it is a start.
I then turned my attention to sage leaves. After trying one sheet which took 5 minutes, I realised they were curling into cigar shapes because of the rib on each leaf. For the following sheets, I pierced the middle of each rib with my thumb nail and that stopped them curling.
I also found that 3 1/2 - 4 minutes was enough to dry them (the rib takes the longest so if you were patient enough, you could remove it and they would dry more quickly, maybe in 2 minutes. I think I might try that next time I do some!
Another thing I found with sage was the oil transfer onto the kitchen paper (the slightly brown stain as above and below). I would recommend you use each sheet for NO MORE than 2 lots of leaves otherwise it might ignite during microwaving.
Here they are (4 sheets worth) crumbled into a bowl then poured into a jar.
Obviously it goes without saying,that you need to make sure the leaves are fully drying before storing otherwise they might go mouldy.