A waggler set up is ideal for fishing slower deeper stretches of river where distance casting is required. String the shot out in shirt button style down the length of the line below the float with a smaller (dust shot) nearer the hook allowing the bait to sink in a more natural manner, and making sure that it is not carried along in the current just below the surface. Start off fishing as close to the bed of the river as possible but if snags become a problem shallow off slightly.
Shorten the depth of the rig gradually until the target species are located, line must be paid off the reel constantly and kept on the surface it is a good idea to use a floating line. Do not allow the float to be pulled under by holding back the line, but do not allow excess line to come off of the reel as this will cause the line to bow and reduce the chance of contacting a fish on the strike.