***Disclaimer*** Jail braking your iPhone or iPod touch will deactivate the warranty on it so if it breaks you will not be given another one free of charge, there is also a small chance that if not done properly some of the apps on your iPod will be deleted- if this happens RESTORE IT.
You can find the tutorial for jail breaking an iPod Here.
Step 1: Using Cydia
There are 5 different sections on the Cydia main page they are: Cydia (home), Sections/ install, Changes, Manage, Search.
In sections/ Install it breaks the apps down into categories games, entertainment, etc. Changes which is just the updates section.
Manage directs you to a page with 3 options to go to- packages (list of your apps).
Sources which you add,
And storage which shows you how much room you have left for new packages. And search, which obviously lets you search for apps.
Step 2: Using WinterBoard
When You Tap on the icon a list of all the themes and lock screens that you downloaded will pop up.
-After you have downloaded a theme/ lock-screen go into WinterBoard and the name of the theme/ lock- screen will appear at the top of the list, click on the name and press the home button, the screen will turn black and say setting language, then type your password in and your theme/ lock-screen will be set.