There's 3 potential things going on here.
1) communications issues: if there is an issue, that has to get resolved. Plug in your tuner and read DTCs; if you read successfully, no DTCs or you found some, then communications is working.
2) readiness and drive cycles: this is far simpler than people make it out to be, but you really need to learn how to get it done on your car. For my Mustangs, I can get them in a ready-enough state within 2 drive cycles, each cycle lasting 6-10 minutes.
(a) reset/clear pcm, load tune, etc. No monitors are ready at this point.
(b) take first drive cycle; I drive 6-10 minutes at varying steady speeds of 45, 55, and 65, steady throttle during these times. This gets most of the monitors ready.
(c) let the car sit for at least 6 hours; this is required for evap tests to be run on the next drive cycle.
(d) do another drive cycle, varying the speeds as above; for me, this is driving to the inspection shop, 10 minutes away; by the time I get there, things are ready (I check before going into the shop to make sure I'll pass).
3) if you are getting multiple O2 not ready's for multiple systems, the rear cats are turned off in the tune, and no matter how many cycles you do, it wont pass.