1)turn the screen brightness down
2)Task killer use it!
3)take off live wallpapers
4)make sure gps an wifi are turned off
1) Ignore numbers 2, 3,...aww hell, just ignore all of these cause none of them are exactly right...
2) Use Auto Brightness and see how your battery time vs screen brightness looks after a few days. I personally use this setting because I am indoors and outdoors on a somewhat regular basis and the phone adjusts accordingly...
3) DO NOT INSTALL AND USE A TASK KILLER!----> Click the first link down below in my signature and read what Google and Android Developers have to say about task killers and how Android handles memory and apps...well worth the read! Also, stay away from Antivirus apps...they are virtually useless unless you just want to waste battery life...
4) Live wallpapers will use some battery...but as long as the screen is off, they are really no more a battery eater than the screen itself.
5) GPS can be On, as long as there are no "background or foreground" apps that use it for updating purposes.
WiFi on the other hand, can save you battery as long as you are where you can connect and utilize the signal...it uses less battery when its connected than 3G. Now, if you dont have any WiFi spots to connect to, then you need to turn it off or it will be constantly "searching" for a signal which does eat into battery life.
6) Make sure you set Widgets that update to the longest possible times, or like myself, set them to Manual Update...that way they arent trying to update every 30 minutes or so.RSS feeds, Weather Widgets and FaceBook and E-mail, all can all be treated the same way depending on how much you need them to update...all of mine are set on Manual.
Doing items 2-6 can greatly add to your battery life. I personally get between 17 and 20 hours a day out of my rooted and ROM`d Droid X, just by doing what I outlined here...
Good luck, and remember, anything from 10-12 hours daily is actually pretty decent when talking about "smartphones" depending on what all you are doing with them...
