/me nods...

One of the best things I ever did, was to sit down and actually read every bit of the documentation page on the CGI module, and then, every bit of the documentation about the drivers I was using.   This is deep material and there is a lot of it, and I read it through twice, resisting mightily the urge to “scan” (or simply, to let my eyes glaze over and Zzzzzz...).   Grab a triple-shot espresso and do the same.   (Fair warning:   it took several days.)