/ 
The two most common shades of insects, and therefore of flies, are dark, i.e. predominantly brown and black, and light, i.e. predominantly greyish.
This general-purpose drowned fly will cover most of the clear insects found in French rivers. By changing its size and playing with the color of the tag and dubbing, you'll be able to create different patterns and build up a fine series of clear flies that imitate most baits.
Assembly sheet
Kamazan B170 hook size 10.
UTC 70 Black mounting silk.
Come to the bend and attach a few fibers of gray pardo rooster.
Then attach a thread of fine silver tinsel, followed by a piece of olive Uni Yarn.
Wrap Uni Yarn 2/3 turns then block. Attach a grey-dun cock hackle (length 3/ 4 mn). Poise its mounting silk and attach grey squirrel SLF spikey dubbing, then shape the body up to 2 mn from the eyelet. Wrap the hackle around the dubbing, then hoop with silver tinsel thread. Attach a grey partridge feather and wrap. Mounting silk head + UV resin.
Tips and tricks
By tying a train of two or three flies, depending on your preferences, with light, dark and/or black shades, you cover all the colors preferred by our trout. It's always a good idea to mount different flies on your leader to find out what they prefer on the big day. Then, by trial and error, you need to make various changes of pattern and size throughout the day to see what takes best. A bit like nymphing, you have to adapt to the conditions and the mood of the fish.
Don't forget to bring your flies to life by varying the animations. If touches don't intervene, play on inciting drownings with brightly colored tags. Sometimes a simple touch of red, green or yellow, or tinsel (silver/gold/pearl) can trigger more touches.
