I think Jeff has the most valuable tip so far - get yourself a digital camera. The instant feedback and the fact that you can shoot to your heart's content is well worth it. It's also handy to refer back to the EXIF data to see what settings were used on a particular shot. You can't do that with film. The other thing you can't do with film is vary your ISO during a shoot unless you have more than one camera.

All of the above tips are good but it's very difficult taking in all the information and making use of it out in the field. It's like having too many swing thoughts in golf - it just screws you up (the golfers will know what I'm talking about). Pick one or two things to experiment with and see for yourself how they affect the results. Don't try to vary too many parameters at once.

For instance, if you are interested in DOF then get a tripod, pick a still life foreground subject with plenty of background, set your camera on aperture priority and take a shot at each available aperture. Make sure you don't change any other settings. Then compare the results making note of the aperture used.

Same goes for shutter speed. Do one set of shutter priority shots handheld on a still subject. Do another set with a tripod on a moving subject. Then try handheld on a moving subject. These are all different situations and what works for one may not work for the other.

A picture is worth a thousand posts. And that's my 0.02.

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