I tend to think of learning perl - or any other programming languages for that matter - like learning a language. You get better the longer your experience is with it and the more you use it.

At the beginning stage, it's a bit like a child learning to speak. The child has limited vocabulary and mastery of the grammar but yet succeeds in conveying his ideas. He'll makes mistakes (over-generation, for example, when he says things that "I eated" instead of "I ate") but overtime, he'll make corrections and become more proficient in the language.

He can do that because of constant interaction with the language. I think learning to program is the same. You start by writing simple programs using whatever knowledge of perl you know at the initial stage. As you become more familiar with the language, you'll discover better ways of coding which had previously not occurred to you. You can hasten that learning process not just by coding more, but by reading books and other people's code.