There are several professional photographers in this forum who will be able to give you excellent tips, but I'm coming from a purely amateur angle.
I don't even own a light tent or a reflector, but what has helped me tremendously are the following:
- Lighting - natural light from shooting near an open window (but no direct sunlight)
- Vibration control - a tripod is essential. Also set a 2 second timer delay on your camera.
- Getting everything in focus - set your aperture to f8-11. Focus on the part of the watch dial closest to you - the whole dial should get in reasonable focus. Experiment.
- Set your camera in manual mode, turn the lens to it's minimal focal distance - that'll be as macro as you'll be able to get.
- With this setup, reflections is always a bitch. You'll have to play around with angles, and once again, experiment!
Hope this helps.

ben
Singapore