Good luck out there!
I tried to make a gingerbread house one year. It was a straight up disaster. I ended up eating all of the "evidence" that night and calling it done.
Making a gingerbread house is a big undertaking, which is deceptive, because it's just a bunch of cookies, right? How hard could that be?
The main thing that you need for a gingerbread house is patience, and a bunch of pastry bag tips. I had neither - I'm an impatient person by nature, and I was just using the cheapskate version of a pastry bag, where you cut the corner off a Ziplock bag.
Do yourself a favor: give yourself plenty of time for your project, and bring the right tools for the job. Remember that several steps will take hours to set, and that you want to leave the house out overnight to firm up before you start decorating it. And for pity's sake, use a light touch!
Once you start the decoration phase, you can tidy up frosting smudges with the corner of a damp paper towel, or with a Q-tip. And don't be afraid to go nuts with the weird candy decorations - that's the best part!