Do an Internet search for "Learn Portuguese" and choose from a number of websites that will teach you the language: Easy Portuguese, E Language School, Learn Portuguese Now, or 101 Languages.
Click through the free language sites, learning popular phrases, articles, verbs, adjectives and every other component of the language. Watch video clips that further help you master the language.
Seek greater instruction with an online course that you pay for. Try websites like Learning Brazilian, Rosetta Stone, or Babbel.
Download audio books related to learning Portuguese and listen to them with your computer.