It's all Greek to me!

I see the patch for the Paypal Express and have downloaded it. However, I am too idiotic to figure out what exactly to do with it now. Where do I copy the files to? I am having similar errors to some posted in this forum but can't make heads or tails of the replies and or solutions because my head is probably too thick to absorb this and the language is foreign to me as I am a novice at shopping carts, htlm, php etc.

Here is my error message: Will the patch fix this problem and if so, where do I install it. :unsure:

Warning: array_merge() [function.array-merge]: Argument #1 is not an array in /home/wholesom/public_html/includes/modules/payment/paypalwpp.php on line 1467

Warning: array_merge() [function.array-merge]: Argument #2 is not an array in /home/wholesom/public_html/includes/modules/payment/paypalwpp.php on line 1467

Warning: Cannot modify header information - headers already sent by (output started at /home/wholesom/public_html/includes/modules/payment/paypalwpp.php:1467) in /home/wholesom/public_html/includes/modules/payment/paypalwpp.php on line 1492

Warning: Cannot modify header information - headers already sent by (output started at /home/wholesom/public_html/includes/modules/payment/paypalwpp.php:1467) in /home/wholesom/public_html/includes/functions/functions_general.php on line 44

Many Thanks from the technologically challenged Hound.