Mix together the oregano, sesame seeds, cumin, and salt in a small bowl, set aside.
Beginning and ending with the salmon, thread the salmon and folded lemon slices onto two pairs of side-by-side skewers. You will have 6-8 total skewers, depending on how close you put your salmon and folded lemon slices.
Brush both sides of the skewers with oil and then sprinkle with the spice mixture.
Grill, turning once or twice during the grilling time, 5-8 minutes, until the fish is opaque.