Well done you!!
My LO used to, and still does sometimes wake early from naps. I just leave her in her cot to play until it is time to eat, or we do a leisurly nappy change and have some nice cuddles. The extra activity before eating doesn't seem to make a difference to her mood / night time sleep.
(I too have an Angel / Textbook baby)
With regards to a routine for getting her to nap, I would start introducing something small that your LO can relate with having a nap. My LO used to fall asleep on her own, no matter where we were. One day when she was about 4 weeks old she fell asleep on the floor in the middle of my mothers group!! When she hit 4 months things changed. She was way too interested in the world to go to sleep, and we hadn't established a good routine. A bit of accidental parenting turned our Angel into a Spirited baby!! Glad to say it didn't take long to get back on track.
I wish I had seen the potential hazard looming (as you have) before it was too late.
Good luck and hope this has helped