Any suggestions for battery life?

About a month and a half ago I purchased an HTC EVO V from Virgin Mobile. I love the phone and all of its amazing features but the battery life has been rather awful. I understand that constant use will run down the battery, but earlier today it dropped from 86% to 68% after playing 10 minutes of Words With Friends. Is this normal? I downloaded the Juice Defender app right after I bought the phone and I'm sure it is helping at least a little bit. I have 4G but usually use 3G unless necessary. When I look under "battery use," it says Screen is using 82% (I have the brightness set almost at the lowest setting), Cell Standby is using 9%, Phone Idle is using 7%, and Android System is using 2%. Maybe I'm just used to not having a fancy phone that eats up battery life, but if anybody has suggestions or tips, I would appreciate it. Thanks in advance!