*It will take a lot of experimentation. My suggestion is to start with a stationary object (i.e. one which does not move between shots) and get familiar with any focus stacking software you'll use (there are free ones available, like CombineZ) before you try something as difficult as a moving object. When I did the image of mealybugs at the left, it drove me half insane, fixing all of the spots where the images didn't line up, or where the bugs had moved between shots (at a scale like that, even a millimeter is too much). If you're doing something like that with software you're not familiar with, you'll get dispirited quickly. —