Best practice: Installing/charging NEW iPhone 4 Replacement battery

Well guys/gals, I'm back again.

A few days ago, I was able to (with some help) determine that my iPhone 4 battery had expired. So, I went ahead and ordered a replacement battery online and was wondering what the BEST way is to "acclimate" the battery to it's new home. Do they come charged? Need charging? Should I let it charge up immediately after install?

Just looking for someone who's done this before and successfully got their phone working like new after a battery install.

Thanks again!