It is useful to begin every script with:

use strict;
use warnings;
use diagnostics;
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The diagnostics pragma puts extra information into warning messages, which can help in figuring what the warnings are really about.

As a rule, concentrate on the first error or warning message and fix it. Often, this will fix the other warnings or errors too.

Here are some helpful references:

• brian's Guide to Solving Any Perl Problem
• Basic debugging checklist
• Coping with Scoping

“Uninitialised” warnings generally mean your variables don’t contain the data you think they do. Get in the habit of printing out the contents of variables. Here is an easy way:

use Data::Dumper;

my %hash;
# Fill %hash with data
print Dumper(\%hash);
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Data::Dumper is a core module, so you have it already. See Data::Dumper for more information.

That’s the best advice I can think of at the moment. Hope it helps,