You’re best friend when searching for rock art is usually the topography & carving tradition. Look at the known carvings in the area & their positions in the landscape, are there any similarities i.e. positioned nr streams / springs, in valleys, on terraces, sheltered areas at the foot of inclines, on knolls / raised areas, close to other archaeological features such as cairns etc. Do the motifs appear on specific surfaces of stones i.e. vertical, flat or sloping (in some areas they only appear on surfaces that slope towards the valley), are they carved on bedrock or free standing boulders (large or small).

Doing this you’ll notice certain patterns emerge & it’ll assist in locating others.