My main doesn't have any telltales and I'd like to add some - is there an ideal number and position for them, particularly leach telltales.
Also do most people use a wind indicator and if so what type?
The best leech telltales are strips of spinnaker nylon ( silicone coated preferably ) sewn on the leech just below each batten pocket. The top one is the most indicative of what is happening.
The Falker Flag is the most used as it has a wire frame so it doesn't flap around.