If any of you people are confused here are the steps you will need to do!
Step 1: Download the folder and have your usb ready and connected into your computer
Step 2: Open up the folder and search until you find the folder PS3
Step 3: Once you found the folder PS3 copy that to your desktop and delete the rest of the folders because you don't need them
Step 4: Now you are ready to put the PS3 folder into your usb stick so please put that ps3 folder into the usb
Step 5: Now unplug the usb from the computer and head over to the ps3
Step 6: Once you are at the ps3 you will need to put the usb in the right slot of the usb slots
Step 7: Once you have done that you will have to go to setting/Theme Setting/Istall[Which is at the top]
Step 8: Click on install and there you will have your custom themes ready to download select one you want to have and it will download and be on your themes and you can go back to install and download another one!
Hope this helping you I have done it myself if you guys want me to make a video I'm more then happy too