Things that I learnt the hard way are humbly offered for your consideration.

Always use warnings; then eliminate any that show up. They are problems waiting to happen.

use strict; think about what variables you are made to define, why and when they are needed;

Find a code layout standard that suits you and then stick with it. The structure so revealed will help you understand your thought processes and show you where you perhaps need to rewrite.

If the code looks clumsy then it can probably be written better. I would write (undef,undef,undef,undef,undef,undef,$wday,undef,undef) = localtime(time); until I found that this should be written $wday = (localtime)[6]; and write code that read lines and assembled paragraphs until I understood 
{
    local $/ = "";
    $header = <STDIN>;
}

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Always bear in mind the richness that is CPAN. Don't reinvent; but reuse, recycle, or adapt.

In reply to Hard Lessons by Odud

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