Congratulations! May the best of your past be the worst of your future.
As to advice:
Set a budget for the wedding, and stick to it (I assume you're paying?).
Despite what anyone tells you, it's okay and desirable to be involved in the process--there will be disagreements, but you'll be invested in it and she'll appreciate that
Register at a place that allows returns for cash--you'll register for lots of things you'll later find you don't need, and for things...