One "way to do it":
- Learning Perl: It sounds to me like you're probably past this point already.
- Intermediate Perl: This may be a good choice for you; references, packages, modules, objects, testing, distribution.
- Modern Perl: This is a nice book demonstrating a more modern philosophy toward using Perl effectively.
- Programming Perl: I had the 2nd and 3rd editions, and wasn't sure the 4th would be worthwhile, but its sections on pattern matching (explaining more recent editions to the Perl RE sub-language), and Unicode have been highly worthwhile for me. It also covers things like security, as well as more modern tools and techniques.
- Perl Testing: A Developer's Notebook: Perl has really embraced the testing culture, and while Intermediate Perl and the documentation for Test::More can get you headed in the right direction, this book helps to broaden ones skill-set (and tool set) for testing.
- Higher Order Perl: This book is excellent. You probably won't want to run out and write a parser using functional techniques as the first order of business after finishing the book, but it will improve your mastery of "higher order" techniques, and this is almost certain to reflect in your code.
There are a lot of other resources. And my list got longer than I originally intended. There are other books I really like, but didn't include, because this list alone is plenty to help you (along with your own research and practice) to get over the next hump or two, or more. :)