In order to survive around water, you need to know how to swim. It is important to be able to do coordinated movements, like steady strokes and powerful kicks. A key tip for steady strokes is to keep your arms straight and fingers together. It will help you scoop better. Also to be a successful swimmer you need to be able to know how to do your breathing position, for freestyle you would probably roll.
It is also essential to know how to float. Something to remember is to keep your stomach up. In backstroke you would have to float, so that is why this tip is handy.