Using it smart.

Turn down brightness.
Turn off 4G if not needed for long periods when the phone is idle.
Turn off wi-fi unless connection is stable.
Turn off background data and gps.

If you need an app to keep the phone almost dead at idle, you can try to Juice Defender or the such, but people tend to have mixed results with battery apps.

My best recommendation other than just installing Basix, or Exodus (and eventually the custom kerenel, which will help quite a bit with the battery) and doing the things I said above, is to go and grab one of the cheapo extended batteries from ebay or batterybay (or mugen if you want to drop 100 bucks) deep charge the hell out of it, and enjoy.

 

Yawa is pretty much spot on. If you want to save battery power. Your best bet is just to manually keep its pwer usage to a minimum.

Juice Defender and Green Power do their job. Unfortunately, (For me) the ability for the programs to toggle on/off 4G suck, which is my main culprit for battery.

Simply put. If you want it done right. Do it yourself.

 

I heard about this app called "Power Max" frm a friend so I just installed it today. I can't say much about it because I havent had it lng enough but it seems to be wrkn so far, its full features are only free for 3 days or so then your stuck with its lowest setting unless you buy the unlock key for $1.99 but I figured I would post this here just incase you wanted to check it out too. Here's a link to it in the market.
https://market.android.com/details?id=com.voltup.powermax&feature=more_from_developer