Just something from a noob on the "bow - turn - bow" part:
To stop myself from going through the motions without any emotions, I made something up to put more meaning into my bows before sitting.
While bowing towards the zafu, my thoughts go along the lines of "Realizing that I can only walk on this Buddha Path thanks to all the Buddhas, Bodhisattvas, Teachers and many other beings
(yes, including the lady at the supermarket who stacks the shelf so I can get sustenance), I bow in gratitude. To name just one of the many, I say thanks to Manjushri Maha Bodhisattva, whose seat I am about to borrow: Namu Monju Bosatsu."
While bowing away from the zafu, I give something like a mash-up of Metta and the Vows, and as I happen to bow roughly in the direction of a Kannon statue, I say: Namu Daiji Daihi Kyuuku Kanzeonbosatsu.
To keep this really heartfelt and alive, I try not to phrase it exactly the same each time.
Now I am writing about this, it made me think of the bow-turn-bow
after sitting: I just came to realize that I usually just get it over and done with. I really should put some meaning into those bows from now on. Thank you for giving me the opportunity to write about it ... seems to help me realizing things.
Sat today, lah and good night
Gero