required attributes

[q-skins.dk]

Hi all. 

Is there any solution of how to make attributes required in PS1.4.8. Some of my customers forget to choose the correct attribute, and they then have to sent back the order which is frustration for me and the customer. I have read a littl about a return false code to the product.tpl file, but can't really figure out how to do that. If somebody know any solution please be helpful to show the detailed solution with changes and line numbers if possible. 

Thanks in advance.