What I'd like to do is replace certain text on a web page based on a user input. For example, I'll have a form that says "enter your user ID", and based on what they enter, certain parts on the page will be replaced with their user ID.
Here is an example of what I mean:
Half way down the page this person has a form that says "brand tools". You fill in the form with your "affiliate ID". Then when you hit submit, all the instances of this text on the page...
...get replaced with:
The xxxxx part gets replaced with the affiliate id you filled into the form.
I'm not very technical at all, so what's the simplest way to accomplish this?