Some apps are true battery drainers, which is why you should use those apps a little less than usual. Once you discover those apps, you may close them, and prevent them from running in the background, by tapping on Home button twice, and removing the up once you find it on the list of recently used apps. To find out what apps are draining your battery, go to Settings > General > Usage > Battery Usage.
You don’t need Bluetooth all the time, and when it is turned on, it drains the battery. Go to Settings > General > Bluetooth, and turn it off.
You probably use one of several email accounts you have, and the rest are just battery drainers, which is why you should remove them. To do this, go to Settings, tap on Mail, Contacts, Calendars, and find the accounts you don’t use, and press on Delete Account.
Automatic update of your apps is useful because all the apps you are using will be updated, but it may have a huge impact on your battery. You can turn it off by tapping on Settings and choosing iTunes & App Store. Tap on Automatic Downloads, and turn it off.
Truth to be told, you don’t need Wi-Fi all the time. Turning it off for an hour or two, when you are doing something else may be extremely useful.