This article will give some useful advice to all swimmers who are already able to do many pool laps, without gasping for air every stroke, so not for swimmers who are still learning how to survive in the water. Contents: 1) TECHNIQUE AND SENSIBILITY, (Explanation of common errors, and answerin the Questin: What causes those first four errors, and the loss of power and how can they be corrected ?) 2) PROPER BODY POSITION IN THE WATER (Explanation of three ways to eliminate drag).