I made some suggestions to another flyfisher recently on how I prefer to avoid tangles while casting and thought that would be a good topic for discussion amongst the group.
The topic being discussed in that case was how to prevent tangles when casting a weighted nymphing rig with an indicator. My suggestion to that person was to make a slightly oval cast, where the backcast is somewhat sidearm, and the forward cast more vertical. I find this keeps the backcast loop open and also reduces the chance that shot and flies will be snapped or thrown off. I should have suggested that the nympher make as few false casts as possible, as this is the most sure-fire way to prevent tangles.
The best way to prevent tangles when making casts with a more normal leader and fly set up is to make sure you aren't throwing tailing loops. (if anyone needs an explanation of tailing loops and their causes, it would be best to consult Doug on that) After that, keeping false casts to a minimum will be helpful in that case as well.
What tips and tricks do y'all advocate to eliminate tangles?