First, start over with the design. You'll just give yourself headaches trying to use a "partial design" from a developer. All developers somehow think they can design dbs, which in fact (virtually) none of them can!

Don't get fancy. Follow the normal steps. Identity major entities and attributes. Don't initially worry about putting them in tables, just get as good and thorough a list as you can.

Then do the standard 1nf, 2nf, and 3nf phases. End with bcnf, or not, or only part of it, whichever you prefer as a DBA. Don't try to short cut either. Normalization is a step-by-step process. That doesn't necessarily mean it's slow, but it's mostly a serial process, not an unordered one.