How do I use the Sun Domain ability "Nimbus of light"?

[Val'Ross the explorer]

I play PFS/PF RPG and mostly Clerics. I have a few clerics of Sarenrae with the Sun Domain. How do I use "Nimbus of light"?
I looked it up in the Rules section and found a post from 2009
"What type of action is it to activate/deactivate Nimbus of Light (Cleric Sun Domain ability)?
Posted Answer: standard action unless it says otherwise.
Myself do not agree. I have served my deity for 8 levels. I think it should be like a Paladin's" Lay on hands-self" Swift action. Was hoping it was updated.
So How do I use the ability?
Level 8 Cleric.(use 8 rounds)
Turn 1. Move action: Get into Position, Standard Action: Activate "Nimbus", {Undead take damage, Darkness dispelled ect. }That is 1 of 8 "uses per day"
Turn 2. Nimbus is still activated (?) I get a move and a standard action.
As my standard action I channel energy to harm undead. Nimbus "does it's thing" 2 of 8 uses.
End of Turn. All undead are destroyed. But Other opponents are still in combat.
Turn 3. I no longer need the Nimbus of light ability. On my Standard action do I De-Activate it? and use another "usage 3 of 8".
Or on my standard action I am free to "cast a spell or attack" as normal.
I am sorry if this seems Stupid but I will be reaching level 8 or play a cleric with this ability and want to Do it corectly. Thank You.

[Gummy Bear]

Unless stated otherwise, supernatural abilities take a standard action to activate. Deactivating should effectively be a free action that you have to make as soon as it is your turn (otherwise you are using it for greater than 1 round). I have no idea how the rules fall on whether or not you have to spend actions each round to maintain it though.

I know it is PFS, but do you consistently have the same GM? If you do, just ask them how they would rule it.

[Val'Ross the explorer]

I play PFS Clerics at Game Cons (mostly different GM's each game) and some PF RPG's on roll20. Honestly all Gm's don't know unless they know All the rules or play Clerics.
The ability starts @ 8th level, I only have 2 PC's that high. So the GM might not have had that ability.
Being a GM is difficult. With so many class/sub classes ect.
I like your reply and think unless at the start of my turn I state "I will de-activate the Nimbus", it is still active. Free action.
Thank you. I just want it "carved in stone" So I have the correct rules.