Some ideas...

• Read "Programming Perl". You'll be amazed at how much perl has to offer that you don't know about.
• Study code written by people who predominantly use perl and do it well. Many of these people hang out here at PerlMonks and often post code.
• Have your own code reviewed by those same people. There are several sections of the Monastery that you can post your code in. Anything you post will be reviewed.
• Look at the modules installed on your system and see how they do things. Download modules that do things you're interested in and examine those.
• Ask questions. If you think there might be another way or a better way, post what you have and ask others for suggestions. Use the chatterbox if it's small snippets of code.
• Occassionally reread "Programming Perl". You'll be amazed at how much you missed the last time. (I'm on my fourth reading and still learning.