All of the above ideas are valid.

Simply thinking about releasing yoour shutter smoothly might help. I know that in the adrenaline pumping excitement of shooting a sporting event or the equivalent - I sometimes am prone to jabbing the shutter button rather than smooooooothly pressing it. I can feel the differance and see the difference in my images when I consciously think about a smooth release.

iI am also a great fan of tripods and jusin a monopod when a tripod is impossible (not just inconvenient).

A tip for monopod use. Carry a strap of velcro about 2 feet long with the hooks on one side and the loops on the other. Use this strap to secure the monopod to anything that is steady (post, railing, etc.). You now have the steadiness of a tripod for an extra ounce of weight.

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Retired Navy Master Chief Photographer's Mate - 30 years service. Combat Cameraman, Motion Picture Director and Naval Aircrewman. Equipment: Canon Ten-D DSLR with 17-40 Milimeter f/4L, 28 to 135 millimeter IS, 70 to 200 millimeter f/4L and, yes the plastic toy lens that delivers great images - 50 milimeter f/1.8 Mark II. Also Canon 1.4 x teleconverter and 420 ex flash.