The first order of the day should always be, 'Stay out of the road crap at the side of the road', if at all possible. Road crap is a legitimate reason for riding the line of the bike lane rather than in its middle, or for taking the lane if you're not being a total pest by holding up traffic behind you.
I ride those very affordable Performance brand tires mentioned in an earlier thread, and have used no other puncture resistant measures. Works great...no flats until...the winter snow and ice arrives. Then DOT throws down that flinty gravel that has a heyday with my poor tires. Around Christmastime, I had about four flats in close succession. Once the road crews got that stuff cleaned up, the flats stopped. Still, this winter, I may have to get some flat protection.
Tires aren't that tough to fix on the road with the rubber cement kit, but it gets old the second and third time in a week. I heard a story somewhere about a bike shop replacing a tube for someone they described as homeless. Said he had more than 25 patches on his old tube.