Properly attached knot is very important to the fly leader when you are catching fish with the help of connecting a salmon fly line to leader. You can also go with an easier method of attaching the knot with a section of empty ink cartridge to get greater flexibility.
You need to first point the end of the fly line as a strong knot attached while connecting a salmon fly line to a leader. You also need to lay some three inches of thick butt end of the leader which will also be attached with the fly line. You need to understand that it is a difficult task to attach all the upper fly line with the leader but still if you show patience, you will be successfully doing the procedure with ease.
The next important thing is to bend the leader with an open pen cartridge for a better grip. U Shape leader will easily bend over for attaching the fly line. You just need to hold tight the leader towards a clockwise direction. Remember to take your time while trying to do this procedure, it will take a lot of practice to master this technique.