A mend is any adjustment or manipulation to your fly line that promotes a more natural presentation. This video is primarily focused on dry fly fishing, but you can mend to help aid your streamers to sink better, swing more smoothly, or sink those nymphs right down to the bottom.
The most important element to mending is understanding WHY we mend so that you can independently problem solve your own challenges during the drift.
Did you miss our previous article...
https://fishingvideos.club/Fly-Fishing/how-to-find-trout-in-a-river-part-1