Some tips and techniques that I've picked up over the years. I don't maintain that these are 'official' or 'absolute'...they are simply my preference and things that have worked for me. I would like to share them here, and leave you to make the decision as to whether or not they fit in your 'code arsenal' :)
This tutorial will help solve the most common undefined variable issues. It is written for the beginner coder in terms that make scopes easily understandable by anyone.
If you are using the CFFORM tag in a shared hosting environment, and why wouldn't you as CF form elements can be very useful, you may now be receiving obscure JavaScript errors when your form loads. Never fear, the solution is a simple fix to an annoying problem