When I had my marriage convalidated, I wore a long white formal dress (not a wedding dress) and my veil from our first wedding. I also carried a fresh bouquet. My husband wore a suit and our son wore a little corsage on his shirt. We had a private ceremony in the Church and invited only close family. We had a party afterwards with wedding cake and champagne. You don’t need to do all of this, but I would encourage you to think of this as your real wedding, even though you are already civilly married. This is important b/c your vows need to be new vows in your minds in order for your marriage to be valid-- making it more like a wedding may help you to do this. Congratulations on your convalidation!