It's pretty straight forward for most phones. Go into your main settings, then find the application manager. Next, select an app you want to attempt to move.* Inside the app settings, look for the move to SD option. If you see it, select it. If the option isn't there, then the app can't be moved.
*I say "attempt to move" because not every app can be moved, depending on how the developer programmed it. Even apps that can be moved don't fully transfer over to the SD card. They will still have some files left on the internal storage, and the amount moved varies by app.
When you do move apps, you'll loose the ability to use any widgets associated with them, and it may start presenting other issues (I.e. Resetting app defaults after a reboot). Because of this, it's generally not recommended to move apps to the SD card. You're better off moving individual files if you haven't already, like your media, to the SD card if you need to free up space.