My favorite fly is any bright color fly with either a cone or bead on the front to get it down or a tiny spinner blade on the front. These fish often react to vibration or noise more than color so take that into consideration when choosing your fly. Dark fly's can work well at times also but bright fly's are normally better. If your state allows it you will deffinately want a dropper rig for whites. With a dropper rig it's not unusual at all to catch two in one cast. Down and across is my favorite presentation for these fish. Also, just around dark if a hatch occurs, dry fly's will suddenly start working for these fish. When they key on a hatch they can be just as fussy as trout.