Is this method ok?

Performed my first kegging this past weekend! I guess it turned out well. Ive read a ton of write ups on how and how not to keg that I just dont know which is the simplest and bet way to do it. Instead of asking how to, Ill just tell you what i did and yall correct or add to what I did or didnt do.
-Racked beer to keg
-sat overnite in fridge (46 deg)
-hooked up CO2 and pushed 40psi
-shook/rolled for 6 minutes
-dropped psi back down to 9-10
-bled off O2 and replaced back into fridege overnite and turned off CO2
Here are my questions, Ive seen different suggested levels of CO2 for the different styles of beer. Which is correct or is it really personal preferance? Ive read that you should shut gass off and that I should leave it on. Which is it? Should I leave it on for the first 2-5 days until it equalizes and the beer is fully carbed, then turn it off? From what ive read, Unless youre really in a hurry, its probably better and more natural to let your beer sit and naturally carb up in the keg instead of force carbing (shaking or rolling menthod). Last question, in the future if I choose to not force carb, do I i simply figure the tempertaure then the level I want, set the regulater at that pressure and let it sit in the fridge for a week or so until it carbs up?

3 things.

Bleed the oxygen out BEFORE you start shaking and rolling.

No need to shut off the gas, if it is set at serving pressure it should not rise above that.

You don't have to wait for the beer to be fridge temp before hooking it up to CO2 but I guess it would make the math easier if you are trying to find your correct volume.

My method...

Rack to keg
Hook up CO2
Bleed O2
Set to 30 and shake/roll for a few min
Lower to serving pressure after about 24 hours
Drink 2-3 days after it is in the keg

** this is what I do**

immediatley after keggging I hook up gas, and purge all air out then fill it with gas, dissconect and let sit until I want to carbonate, usually immedately. Typically I will let tthe beer sit 3 days with 30 psi. Less psi = more time, this decision is up to the brewer. Then bleed off CO2, turn regulator down to serving pressure ~8psi (depends on your system, lines, temp, etc...) then hook gas up, turn on then pour a pint.

Kegs should be treated like babies, the impatient shake babies