Didn't have time right now to watch the whole thing. It's over an hour-long, which in itself seems unusual for such a simple scene, but that's ok. Everyone has their own way of doing things I guess, and it doesn't hurt to learn different techniques. However, if I were going to model an object and create a scene to real-world units of measure that were significantly smaller than the default Blender scene units (meters), I'd definitely change the scene units to match the units of that object I'm creating. In other words, if the cup reference is calling for dimensions in millimeters, then I would change the scene units and the grid units to millimeters in Blender, rather than using scale formulas to convert and scale everything on the fly as he is doing there. However, that's just a personal workflow preference. It's not necessarily incorrect to do it the way he is doing it, and some people might argue that keeping the scene in meters will make it easier if you decide to start creating other things in the scene that use a larger scale.

The only other thing I noticed while scrubbing through is that he's really doing a lot of things the "long" way, so to speak. It may sound like nitpicking, but many of his polygon selections in edit mode were done in a much slower, longer way than might be necessary. For example, when he selects the polygons for the white material on the cup, he was using box selection from the top view, which doesn't capture all the necessary polygons on the model, so then he has to manually select those additional polygons by hand. There is a much, much faster way of doing this. In fact, there are a couple of different methods I can think of which would do a better job of selecting all those polygons more efficiently, but I don't wanna explain all that right now because it could confuse you during this project. There's nothing inherently wrong with the way he's doing things, it's just some of the techniques seem unnecessarily complicated.

I certainly do not wish to critique this video or his workflow. I just want you to know that there are faster methods to doing most of this, especially the modeling process. As far as "bad habits" are concerned, I don't see anything offhand to worry about. The tutorial seems to produce a nice product in the end, and that's really what it's about unless you are an advanced modeler or content creator.

Have fun with it!

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