How should I treat the iPhone's battery once unboxed?

Once I unbox a new iPhone, what should I do with it? Charge it for a few hours? Or use up the available battery?

Don't use it while on charge, that wears out the battery.
Don't charge it all night if it is above 50% because it shouldnt be charging after reaching 100%.
Try and keep it in not to hot places.
So overall just use it up and when it is nearly dead charge it up again.

I'll tell you what I do, and I have never had a battery issue with any iphone I have owned. I charge it when it drops below 20% roughly. Sometimes when under 30% or under 10%, it varies but thats about the time I charge it. I almost always charge it overnight when sleeping (I never turn the phone off, I just flip the mute switch in the corner at night). All that talk about don't overcharge is all b.s. When it comes to iphones, they don't have those issues. I also have used it fairly often while charging, not alot but some, and no issues for me. Out of the box I would just use it as is unless it already shows low battery, but when it gets down to 20% I would charge it overnight as stated.