Getting your camera to be still while you take a picture is one of the most important things you have to master to improve your images. Tripods are the most stable way to do this but they are cumbersome. I hate being nailed down like that. I can't even sit on the couch for 2 minutes without having to get up and move around. It drives my wife CRAZY. She has threatened to install locking seat belts on our furniture to keep me sitting in one place long enough to have a meaningful conversation. Needless to say, I use them when I must but tripods are just not my cup of tea.
So here is what I do most of the time when I'm shooting shutter speeds under 1/60th of a second. I set the strap length where I can slip it over my elbow, lock my wrist and put tension between the camera body and the palm of my hand. (Thanks to my co-worker Gary for taking these snapshots without asking too many questions)
Then I pull my elbows up tight to my body, squeeze down on the trigger as I breath out and hold it down for a fraction of a second after the shutter trips.
SQUEEZE THE TRIGGER - This is a side note to the strap technique but it's so important. Have someone watch your finger and keep practicing until they can't see it move when you take the picture. If you are a firearm shooter this will all make sense to you. Creating the tension on the strap is like pulling the rifle stock back into your shoulder. It's very important but you also have to concentrate on releasing the tension in your body and squeezing off the shot rather than jerking the trigger. I can hear my Dad now, "squeeze the trigger son, don't jerk it, just squeeze it gently. It ought to surprise you when it goes off. Just squeeze it a little harder and a little harder until it goes off..."
I don't know if my father has ever taken a picture in his life but everything he taught me about hunting and firing a weapon applies. If you don't breath right and you don't squeeze right the picture gets away.
The first time I tried this I was amazed at the difference it made in my photos. So, cinch up your strap and give it a "shot." Please post a comment and let me know if it makes a difference for you. If you have other tricks to stabilize your camera while shooting, please post those too.