Start by slicing each nori sheet halfway up the center. This makes folding the wrap easier and ensures all ingredients layer evenly. Prepare your avocado, cucumber, and onion slices while keeping the salmon ready.
Lay the ingredients on the nori in four quadrants: lox, avocado, red onion, and cream cheese with cucumber slices. Drizzle Sriracha and Kewpie mayo over the avocado and sprinkle sesame seeds across the wrap. I find doing this slowly helps everything stay neat.
Carefully fold the layers toward each other, starting with the lox quadrant. Continue folding until you form a compact square wrap. Using a rolling mat makes this step cleaner, but your hands work just fine. Chill slightly if you want a firmer bite.