Hi Nick;
If you can find an older SIG catalog, there was always a section on how to finish a model in dope. That would be a good primer for you as it sounds like you are building a profile model of some sort that is solid balsa. You might want to check the SIG web site and see if they have those pages some where, as I think I remember seeing them at one time. Add to that what you can find to read in the finishing section. You have the right idea in the basics, in that sanding plats a big part. Sanding correctly is the key. Check out any Windy Urtknowski videos that you can find in YouTube on finishing in dope. There is a small ground of us working to upload as many of Windy's videos as possible, and one of those that is in the early mix is the one specifically on finishing in dope. Kevin King of the list here, who lives in Canada has been doing a lot of work on these and has a few of the videos post on the open forum. Those should lead you to the YouTube channel that he is building from a collection of tapes that have been and are being converted from VHS to digital. The short story is, you need to learn what types and grits of paper to use, and the types of tools to use them on. Things can still be dome the old fashioned and and there are newer methods being developed using mire modern materials. But the basics are the same. There is no such thing and shine in a can! It is only the result of proper application of some elbow grease!
Welcome to the group!
Dan McEntee