Possible Clues:

• With 40-Across, headwear for doing laps
• What to do in a pool
• One way to travel
• Take a dip in the pool
• Make waves, say
• Float — feel dizzy
• Dip some wafers, imagining moist surfaces
• Stroke, stroke, stroke...
• Crawl, perhaps, inside nuns' wimples
• Take more than one stroke!