Potty training was a lot harder than I ever expected. To tell the truth, you might be a bit overly optimistic in trying to get a 3 year old to be dry through the night.
Yes, start with nothing to drink an hour before bedtime.
Yes, wake them up in the middle of the night to go potty if you're going straight to big girl pants.
With our oldest, she was a lot closer to 4 or so before she was dry through the night and even still had the occasional accident if she was extra tired from so much activity a certain day. We ended up resorting to letting her "outgrow" the size of pull-ups she was in. She wanted to wear them so she didn't have to worry about having an accident. But then they started getting a little uncomfortable to wear at night, and she'd say they were a bit tight. I'd tell her she could wear her big girl pants, but she'd have to be sure to get up and go potty in the night. She said, "okay...but I want to use your potty" I don't care which potty she uses, as long as she doesn't potty in the bed! LOL Yeah, mine's further away than her bathroom, but that's okay. That was pretty much it too.
ONe thing I've noticed with her is that if she starts to get real fidgety in the middle of the night....if she's not too hot or too cold, then it means she has to go potty.
Just last night, (she's been a little sick lately so she's been in my bed, and DH has slept in her room with the 2 year old) she was real fidgety around 2-3 a.m. I asked if she needed to go potty, and she got up and went, came back, and went right back to sleep - no more fidgeting.
For what it's worth....and good luck!