Shaved Handle Questions

I just have some questions about shaving your door handles.
Where and how do you install the button to open the door, and what happens if your battery is dead? Also, if it's just a button cant anyone just open my door?

This is regarding a 99-00 Civic Si if it matters.

Usually people install it on a remote, and it's just like a remote trunk pop. And if your battery goes dead then you're screwed. Some people install a hidden button on the car (usually connected to a second battery from what I've seen on most cars) so that if their main battery dies then they have this one as a backup. Ever seen Gone in 60 seconds where they're stealing one of the old cars (I think it was the one at the casino) where they find the hidden button inside the front fender? Same thing...