Go to the PlayStation®Store with your PlayStation®3.
You'll need a PlayStation Network account.
Once you're in the PlayStation®Store,
search for SingOn from the top left corner.
Once you're on the product description page
simply select "Download" from the left hand side.
Start SingOn and select ”BUY A TIME PASS” in the Home view.
Choose the Time Pass you wish to purchase from the PlayStation®Store.
Once you've chosen your Time Pass, purchase it by selecting "Buy Now" on the left hand side of the screen.