From Wikipedia:
It was first released as a single on November 3, 1972 [...] The song is deliberately meant to sound to its intended Italian audience like English spoken with an American accent. The song was produced with the purpose of exposing Italian pop artists and musicians who were deceiving the public, pretending to speak/understand english lyrics and plagiarizing American and English songs, so this was a satirical parody to underscore the fact that those artists and musicians were not fluent in any form of English at all, and the Italian public would accept and popularize any song sounding like English, whether or not it was accurate.
To make a long story short, the lyrics don't mean anything whatsoever. Brilliant. Satire at its' finest.