Put the lettuce leaves in a bowl. If they are whole, tear them up.
Using a sharp knife, remove the orange peel together with the white part in a circular motion.
Then cut out the segments between the membranes.
All this is done over a bowl of lettuce leaves so that the resulting juice gets there.
Cut the cucumber in half lengthwise, then cut diagonally.
For dressing, mix the oil and vinegar. It is convenient to do this in a small jar that closes with a lid.
Sprinkle the salad dressing, sprinkle with sesame seeds, salt and pepper. Mix gently.
