A Pro Surfer:
Outward gesture that can be easily trademarked. Do it repeatedly. Adriano has the double-fist triple-claim. Parko has the ten-finger claim. Neco Padaratz claps for himself. Etc.
A Soul Surfer:
Pull off, paddle back out, and say nothing. Later discuss the wave in metaphysical terms.
Make lewd gestures that should offend anyone in the water. Or just mimic your favorite pro surfer's claim.
For the moment, let go of your emotions--laugh, hoot, scream, and make hand gestures. Then spend the rest of your day wishing you hadn't.