Ask yourself what are your goals/vision on photography your answers will guide you though your journey on the streets.
Well said, really most occassions answers would not be clearly defined till later..but we have to read up & be more inquisitive on what we see & hear during our shoot on the street abt what the people we meet are doing.. i once managed to request to be allowed into someone's illegal thingie, i promised no photos in there but heh.. i learnt something that day.. later still manage to get a portrait shot of them(outside of their 'restricted' area ofcoz..)
http://www.flickr.com/photos/dtoh/