When should I start taking the pill?

So I got my birth control pills on Monday. The pamphlet says I should start taking the pill on the first day of my period but my period hasn't come yet. I know it will come soon, within the week if not sooner since I got it around this time last month, but I have never exactly tracked my period before so I'm not 100% sure. Can I start it today even though I'm not on my period yet? If I do, do I have to wait a week before I can have sex w/o a condom? Or 48 hours?