The first thing the two of you may find yourselves planning and paying for together is the honeymoon. While there's no average amount people spend on this once-in-a-lifetime vacation — there are just too many options out there to get an average — most couples do set a budget for the honeymoon as they begin to think about where to go.
Once you've set your spending limit, ask some questions to find out what each of you likes — and where you have common ground. Do you and your intended want a relaxing, tropical getaway, or maybe a romantic inn nearby, or are you going to slough off the coil and travel the world for six months? Whatever your desires — and your budget — look around online for ideas and deals. Or, consider a honeymoon registry, which gives your wedding guests a way to help pay for your trip.
Keep in mind some of the incidental costs as well, from fun items like special lingerie to more mundane, though essential, things like the cost of a visa if you're going to a country that requires one. If you can stick to your budget and plan a trip that both of you will remember for the rest of your lives, you've taken a huge step toward not letting money be a problem in your marriage.