Joanne,
I am kind of in a similar situation to yours, except my ds won't be 10 weeks until Friday. But the nap situation has been very much the same for us, and I have found that I have to put Noah in even before he seems sleepy. I feed him, I talk to him or play for 10 minutes or so, and then it's right in the cribby. Now, this is only my second day having ANY sort of success, but I will say, I have low expectations for the length of his activity time.
As far as shush/pat, I find if I hold Noah firmly as he lays in the crib, he prefers that. I put one hand on his shoulder and the other on his opposite thigh, and just hold on pretty tightly so he can feel secure and, more importantly, not startle. I do this until he gives me the mantra (kind of a throaty gurgle) and then I walk out.
The more I rock him, pick him up, even offer him the pacifier, the worse I make it. It's sort of like how if you set him in the swing or bouncer for awake time, you turn around and he's snoozing. I set him in the crib, and he falls asleep.
Again, this is day 2. Hopefully our experts will come to your rescue, but this is what worked for me.
Good luck!