You should by all means get the free "Just Married" button available at the guest relations offices and ticket windows. The bride and groom Mickey ears are a nice touch too. You're certain to get some friendly hellos and attention from both cast members and other guests.
Beyond that, you should do whatever appeals to you and your hubby. If you're sporty folks, reserve some golf or tennis. If you want to relax, try a couples massage. If you enjoy fine dining, book reservations at one (or more) of Disney's signature restaurants. If you like live music, try Jellyrolls or the House of Blues. If you love silly fun, then by all means try Mickey's Not So Scary Halloween Party. The whole point of the honeymoon is to enjoy each other's company in the way that suits you best.
That being said, it being your honeymoon and all, I'm sure that romance is on your agenda. I'm going to point you to some tips the panel has given to guests looking for romance at WDW and maybe that will give you some ideas.
My tips:
HERE
Laura's:
HERE
Kims's:
HERE
Kara's:
HERE
Darcie's:
HERE
Have a wonderful honeymoon trip. Take lots of photos so you can show them to your kids when you take them to WDW in the years to come :-)