Body scanning - right way of attention moving

Practice - Mindfulness of body When I move attention part by part in the body I don't feel sensations in every part . Is this right ? Or should I feel sensations in all body parts ? Sometimes I do quick sweep of attention from head to feet . I do this at any moment during the day when I remember to be aware of my body . Would this be helpful for practicing mindfulness of body ? Or is there any better way of doing this ?