How do I use Lingopolo to learn a language?

Lingopolo organises lessons into sets of words, and trains you to understand these words by quizzing you with flashcards.  Each quiz consists of 10 words.  At the start of each quiz, you will be shown your current knowledge of the set of words, and at the end of each quiz, you will be shown your new knowledge level.  The idea is that you move each set of words along from having a starting knowledge of 0% to the point where for each set you have a knowledge of 100%.