We just finished covering this in psych class, so here's some advice.
Contrary to popular belief, it's totally safe to wake a sleepwalker. It's just a dick move because sleepwalking happens in the deep REM stages of sleep, meaning it's like waking someone up four hours into an eight hour sleep cycle. As for tips, have your wife or parents lock every door and window and hide all keys, knives, guns, and household cleaners from you. Make a commitment to not go out during your bedtime, as sleepwalking you can be pretty damn convincing. Take note that while it will seem like you're having a normal conversation with someone, a good way to detect if it's sleepwalking is if the sleepwalker says something really freaking out there. So be careful if you're keeping any secrets. Finally, go see a professional if you're certain that you're sleepwalking. It can be a very serious matter (especially if your house has stairs).