How to use PlayStation Gift Card - From your PlayStation home screen, go to the PlayStation Store. then after that Once you're in the PlayStation Store, scroll down until you find the Redeem Code section. On the Redeem Codes screen,then you will see a box in which to enter your code or PlayStation gift card number. To Redeem once redeemed you can use it to purchase games and other digital items on the play station store.
PlayStation gift cards can be purchased from a variety of places including amazon and ebay as well as in certain stores including walmart in the gift card section. Gift Cards range from $10 dollars to $150 . Playstation also has playstation plus gift cards which allows you to gift someone a PS Plus subscription where they can stream video games live to there Playstation without buying the games, these gift cards range from 1 month to 1 year. Gift cards also sometimes provides discounts depending on where you are getting it from that allows you to purchase the same item cheaper through the gift instead of directly through your visa card etc.
Whether or not the playstation gift cards are worth it depends entirely on where you get them from some stores provide you with discounts while others might upcharge you but a couple of extra minutes wouldn't hurt so take that time to look around for the best deal possible.I also think that it is better to get the Playstation plus subscription as it allows for you to play games without buying them.