Surface swimming is easier on your back with a partially inflated BC and without a snorkel.

How to Swim Efficiently on the Surface

Good divers spend as little time on the surface as possible, yet there are times when surface swims and rest breaks are necessary or problems are best solved at the surface. In these cases:

• A properly weighted diver with a correctly fitting BC can float easily on the surface. It should not be necessary to inflate the BC fully; in fact, BCs are often less comfortable and may restrict breathing when fully inflated.
• Surface swimming is easier on your back with a partially inflated BC, so your lungs are at or above the waterline (breathing is easier without water pressure on your chest), and without a snorkel (snorkels increase your work of breathing more than regulators).
• When swimming on your back, know where you're headed. You can do this by using a landmark behind you, using your compass in reverse, looking over your shoulder once in a while or alternating face-down swimming with your buddy.