Stop being like 90% of the dummies out there trying to cast to the other side of the river. While it's fun to cast long, if you are FISHING, keep this in mind.

"The illusion of your fly lifting up from the bottom structure, is perhaps the deadliest element of your presentation."

You'll see and hear a great explanation in the video, but some additional text is critical here to further understand one basic principle. If you can create the illusion that your fly is a critter that originated from the substrate along the bottom, a mature trout that witnesses it is MUCH more likely to eat that fly. MUCH more likely.  

What You Might Be Doing Wrong in Trout Spey

If you are casting too far it creates a multitude of issues with your presentation. The most critical might be that IF you do manage to execute a perfect cast, your fly will sink, then rise waaaayyy out in the middle of the run. While there are certainly times to make a full send, more often you'll want to make casts that you very intentionally sink, drift, and then imitate a rising fly that lifts from the bottom in the fishiest part of the run you are fishing. If you see boulders, structure, or a seam that is extra buttery - plan a very intentional presentation.

Tips to Consider:

• Shorten up, make absolutely perfect casts.  
• Plan for your fly to "tension up" right in front of where you think the trout are holding.
• Focus on making the initial lift and transition from slack to tension as smooth as possible. IMO this is the most important part of the entire presentation.