Here is my thoughts. If after 10-15min you can't get to sleep just get him up and try again 10-15min later. I wouldn't try from 645-815 to get him to sleep. You'll just drive yourself nuts. And yes I would definetely start a routine. What we do for naps is when I start to see signs of tiredness we go upstairs dim lights, i'll rock a little till she's very drowsy but not fully sleep and sing a song than put down and shush/pat until asleep. For Bedtime the winddown is a little longer. We do bath or quick wash with wipes, sing, a book, rock and feed then asleep.
Have you checked out the EASY board for sample routines?