How do I backup from a previous date?

Recently I was going through some old notes. I deleted an important list from part of my notes. I was very sad and frustrated at this. I went to check if my notes were backed up and they were. Now I checked again and it says they have backed up.

I need to know how to restore my iphone to a previous time when it was backed up.

I dread the answer. if you back up a phone, is the previous back up deleted? because i need to restore my phone to the way it was on friday or thursday.

How do I restore notes (or whole phone?) to a previous back up?