I keep a swimmer's towel from REI on the trike - an artificial chamois cloth - for just this task. Notice the puddle of water under the wing tip. When we got the new wing last year, we took Aeros' strong recommendation to get a dacron leading edge instead of a mylar one. This is where it paid off. Water soaks into dacron but beads up on mylar. The leading edge is the most critical part of the wing, aerodynamically.