An umbrella insurance policy is a good place to start, but won't cover everything.
Wrapping stuff in an LLC or corporation will not protect you, if you're the only one in it.
The basics are:
1) Have insurance
2) Be careful
3) Get a good team of professionals, and attempt to understand what each team member does.
In my experience, noone watches over my money better than I do. I educate myself as much as possible. I leave as little as I can to the "pros". When I do need help, I ask for it, and ask a lot of questions.
It's time-consuming, but it's the only way I've found that works for me.