that worked very well for me in Norway on the river Glomma last summer was in imitation of the small Baetis...
It was tied on a size 24 dry fly hook and the grayling just could not et it pass without having a close look and very often a fierce take:
Tail: Micro fibbets, tied split
Body: Orange tying-thread, Danvilles 6/0
Wing: a bunch of CDC fibres, tied in without the stem of the feather.
Highly recommended when Baetis are around....
In this picture the fly is sitting on my finger....
Good luck, Hans