Leaders are the tapered/tapering nylon/fluorocarbon/co-polymer line that attaches to the fly line at one end, and the fly at the other. You can buy ready made tapered leaders, and attach a suitable strength section of nylon to the end, to which you then attach the fly. However, it's just as easy to make your own stepped down leaders, most being made in 3 - 4 or 5 step downs. As a rule the step downs should be between 2 to 3lb difference between each section, thus an example of a three section leader would be :- 4ft of 10lb nylon, 4ft of 8lb nylon, 4ft of 6lb nylon ( 10 - 8 - 6 ) and dependant on droppers etc. Droppers, are the means of attaching more than one fly to the leader/cast. They are one of the nylon ends after forming the joining knots, when making your leaders. ( the other end being cut of! ) I prefer the lower end, some people favour the upper end.
Hair Stackers.
Basically a hair stacker is a tube with a closed end. These can be bought or "Home made" Home made stackers can be produced from :- Copper tubing, plastic tubing, the larger biro outer case, etc, etc. The hair is placed into the open end, and then the closed end is gently tapped to get the points to align in the tube.
Tying Hair Wings.
1) Try and keep the tips even by using a "hair stacker" 2) When tying the hair wing in ensure the hair is tied on the top of the hook, if satisfactory, add a drop of either super glue or varnish, and bind down evenly.
Good Presentation.
1) Try and STOP the rod in the vertical ( or just past vertical ) position abruptly. 2) Allow enough PAUSE for the line to straighten behind you. 3) Then, on the forward cast Stop the rod fairly high. This makes for a nice tight loop of line, which will turn your cast and fly over nicely. 4) DON'T try and cast too far, better to aim for QUALITY of casting, rather than messy distance. All too often anglers try to cast further than they can manage, better to relax and achieve a reasonable distance with NO disturbance, rather than a great SPLASH that scares fish anywhere near your casting area.