This quote from Nuno Oliveira is worth repeating, “the hands receive the work of the legs”. If the rider is using the legs well with tact and timing, the horse becomes light in the hands. If the leg is not well times the hands become strong and there is no lightness.
The horse must be able to respond to the lightest of aids and then the rider must cease the aid, and allow the horse to continue in the same frame, only giving an aid when a change is required. The timing and co-ordination of aids is important, if the legs say go, the hands and seat must not block that aid
With a hot horse, your legs must remain softly against horse’s side and touch lightly or the horse will be surprised by the leg. Don’t clamp your legs on or your horse can’t breathe
The leg positions for different riders may not look exactly alike, dependent on their leg length and the shape of the horse. The pictures below riders with correct leg positions, but each looks slightly different.
Diane Followell Classical Dressage Trainer