For practical instructions, you will need someone with deep knowledge of the practie, like Ven.Thanissaro Bhikkhu:http://www.accesstoinsight.org/lib/auth ... ml#part2-bhttp://www.accesstoinsight.org/lib/auth ... #varietieshttp://www.accesstoinsight.org/lib/thai/lee/inmind.html
As for the term 'parimukhaṃ', there's a relevant thread:viewtopic.php?f=23&t=5636
'Sati' is to keep in mind the selected area of experience, while 'sampajanna' notices aht happens there:viewtopic.php?f=23&t=4299viewtopic.php?f=23&t=5570
The 16 methods of Anapanasati are not a sequence of steps, they are brought together in four groups according to the four ways of establishing remembrance (sati).
The sequence is explained, for example, in Mahanama sutta:
"And when the mind is headed straight, the disciple of the noble ones gains a sense of the goal, gains a sense of the Dhamma, gains joy connected with the Dhamma. In one who is joyful, rapture arises. In one who is rapturous, the body grows calm. One whose body is calmed experiences ease. In one at ease, the mind becomes concentrated."http://www.accesstoinsight.org/tipitaka ... .than.html