When are the hands shaking? When you load the needle? When you approach the tissue with the needle driver/pickup? Is it both hands or just the pickup or needle driver? Different strategies. If it’s just when loading, it’s probably from trying to load in mid air. If it’s all the times probably just nerves, so just practice/take propranolol/ recite a mantra in your head/do a breathing technique.
My general technique: stand up straight, roll your shoulders back, tuck your elbows to your sides gently. Feet shoulder width apart and legs relaxed. Load your needle on the field, and in fact load it on the patient not in mid air. If you are working with a castro type needle holder and finer suture, move your fingers the most, then your wrists, and your elbows and shoulder shouldn’t move very much at all within a bite (might have to move to reposition in between bites). With the large needle drivers, the turning motion is made between opposite movements of fingers 3-5 together and your thumb, with a gentle turn of the wrist. The pickup of your choice is held more like a pencil between your thumb and first two fingers. Don’t forget to breathe!
And I agree, coffee (particularly on an empty stomach) makes it much harder.