Obligatory "Don't Talk to the Police"
If you're not in the US, it's worth checking out what your own local jurisdiction expects - all the items in the Don't Talk to the Police video still stand (because they're about human psychology, not points of law), so it's worth knowing how much you can just shut up around police.
https://www.judcom.nsw.gov.au/publications/benchbks/criminal...
http://www.sydneycriminallawyers.com.au/blog/police-want-fur...
http://www.legalaid.nsw.gov.au/publications/factsheets-and-r...