Now with brevity simplicity in mind, I would simply like to share with you a quick 3 step youtube strategy involving selling your own digital product:
You obviously have many methods of market research you could use, but for this context I recommend finding any problem people have for which a video could provide an appropriate solution, or at least in part. You will want the product to ultimately satisfy their need, of course.
Quick tip: if you can easily attach the words "how to" to whatever people want to do (ie: how to cook), then that's probably a good choice.
You may also wish to survey the book section of Amazon for any existing products on your subject. That's a good indication of commercial viability. This is also a good place to find more product ideas - you just have to look.
Go to your favorite keyword tool and try to find a handful of search terms with a few thousand searches per month. I usually prefer exact match. Keywords containing "how to", while not absolutely necessary, can be preferable as they make fantastic keywords on which to base your videos.
Creating Your Content
You can easily have a product made by hiring are reputable writer. It's a pretty straightforward process, but be sure to clearly define what you want in any case.
So how do you make the videos? Again, that's up to you. But in my opinion one of the best videos you could make for this purpose are ones that directly help the user with on screen instructions using a "show and tell" approach. I think these are the videos that these kinds of viewers value the most.
Even if you can't make the video yourself, you could go to a related forum or even a fiverr gig and negotiate with people who are both willing and able to make the videos. They probably won't offer this up front, but you can always ask. I've pulled this off, so I know it works.
Now that you have some stellar, high traffic videos, you should start sending people to a landing page where you can sell your product at a reasonable price. I'd prefer not to expound on this too much; there's already a lot of information here and elsewhere. However, I promise you can use a really simple page to get the job done.