Boil the potatoes, finely chop the dill, cut the salmon into bite-sized pieces. Mix the dill, salmon and sour cream, season with salt. Peel and dice the potatoes while they are still warm and add them to the sauce. Let soak in the refrigerator for an hour. Occasionally stir gently and before serving, if necessary, dilute a little with milk, as the potatoes soak up all the liquid.