Focus stacking with a Canon EF 100mm f/2.8L Macro IS USM Lens

Any one have any tips for focus stacking. I am using my laptop to focus with the Canon EOS Utility. How many photo should I use for focus stacking? Lets say I am taking picture of the face of the watch on a flat surface. Would ten focus steps and six picture be enough? What have you used? It is taking so long to navigate in 10X zoom on the screen then focus on the watch face. The screen centering is so slow with the Canon EOS utility. Perhaps there is a better program with a faster work flow like Macro DSLR. Unfortunately it is IOS only any one know of a good tethering program for controlling the camera via your PC laptop?

I'd be interested in this myself. See if there's anyone out there with some suggestions..

Each picture would be at different focus, so for ten focus steps, you would need to take 10 pictures.
You would then need to do the actual stacking/compositing in post-pro (using something like photoshop).
I haven't done this, but have watched my better half...

Edit : actually, now that I think about it, there was some tool to do this automatically, but she has got a nikon, and i remember lots of cursing with the tool...sorry to not be of much more assistance.

The more pictures, the better the quality of the resulting image. A macro rail could help in incremental focus adjustments, otherwise you'd have to rely on your lens focus ring. But still could work. Then process images using a stacking software, maybe have a look at Zerene Stacker or Helicon Focus.