Bonus Tip:
If your camera has a Mirror Lock-up function this in addition to the use of a shutter release will remove much of the mechanical vibration your camera itself can create. The mirror in the camera box of your dSLR allows you to see from the viewfinder out your lens. When you trigger the shutter the mirror will flip up out of the way so that light coming through your lens hits the sensor or film in your camera body. Mirror Lock-up will prompt you to trigger the shutter twice, first to move the mirror into a ready position and second to open the shutter. After the first trigger of the shutter you should wait 2-5 seconds for the internal mechanics of your camera and resulting vibration of your camera to settle to the point of being still before you trigger the shutter a second and final time.