I'll bring up gear later. But, a nice technique I've learned is focus stacking. Especially helpful for small parts and when a lot of magnification is used. It helps to get more of the subject in focus. A single shot will not have as much DOF as multiple shots "stacked" together that were taken with multiple points focused on.
Here's a method I used
https://photography.tutsplus.com/art...p--photo-12621
Single shot:
Focus Stacked shot: