We have written many times about how to rig and fish a dropper rig. (See here for a bunch of posts on the subject.) Here’s a great, basic video from the folks at Western New York’s Twig ‘N’ Timber Archery. I agree with the host’s main point that, usually, simpler is better. If you’ve never tried fishing two flies before, this video can get you started.
Note: The illustration in the video (shown below) is by the late, great artist Larry Largay, and he created it for an article that I wrote for American Angler many years ago. Small world . . .

Unreal that you stumbled upon my videos Mr. Monahan! I am a LONG time fan of all things Orvis, and this is very humbling and flattering! Larry Largay’s image is by far the best illustration created to date (IMO) that assists in explaining the concepts presented. Again, thank you from a BIG fan!