Another problem you have (unless you've had someone take a video of your stroke) is that you can't see what you're currently doing, so even if you know what your swimming should look like, you probably won't know whether you're doing it, or how to correct it if you aren't.
I's suggest getting the 1.0 Effortless Endurance Sell-Coaching Course, which is available through this site:
http://www.totalimmersion.net/store/
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