CMOS

There probably could be nothing better you could do than get some swim instruction/coaching. You could hook up with an individual coach or perhaps you could find a club that swims as a group and offers coaching at the same time.

Proper technique is VERY important (if not the most important thing) in swimming. The only way you will probably be able to know what is wrong (and right) with your stroke, and what to do to make it better, is to get some feedback and ideas on what you can do to improve.

Take heart, you are not the only person who started with "swimming like a rock".

Good luck

chrisuletz

Now, I have a couple of months of experience with this, so my main advice is: Get some lessons from a coach. I only took 3 lessons so far (with many swims on my own in between), and I saw a huge improvement. Before, I couldn't freestyle more than 400y continuously, now I just swam 800y. Before, 50y would take me about 1:20, now I averaged 1:05 over those 800y.
I got the lessons at The Atlantic Club, $32/lesson, I assume the prices are pretty much the same anywhere, maybe less if you're a member (I'm not a member there).