1. Lowest Interest Rate: Get the lowest rate card possible, period. A credit card is a debt instrument, and getting a higher rate card on the premise you will get "rewards" is nothing but a trap. A bear trap, waiting for you to step in it. And no, there are no exceptions to this rule, so please don't try to debate me on this.
6. Know Your Statement Date: Mark this on your calendar, so you know when your statement comes out. Check it carefully. You should be checking it online (see below) anyway.