What I did to set the collimation of my laser was to first have a dedicated 1.25" to 2" eyepiece adapter, in other words an adapter you leave on the laser, I replaced the thumb screw with a socket set screw so I wouldn't be tempted to change it.
Then I placed the set up into my scopes focuser and slowly rotated it around and around, stopping every revolution to make an adjustment to the laser until when I rotated the laser & adapter the laser dot on the mirror was centered in the mirrors center spot/mark.
Then I removed the set up and set it aside for a bit to take a break from all that tweeking,,,,,,about an hour and a half's worth, then I put the set up back into the focuser to check that it still hit the center and when rotated it didn't walk around in the center spot of the mirror when I rotated it.
Now I can set my laser set up in the focuser draw tube anytime and know it's accurate.
So does all that effort for accuracy need to be done?
I use the Barlow'd laser collimation technique, Olof Carlin developed it, for that technique to work all the laser has to do is bounce back a shadow of the center mark to be seen on a screen, just because the laser is so accurate doesn't mean the rotation or the tilt of the secondary is precise, it's close but for precision you need to see the center mark reflected back and forth between two mirrors, the primary mirror and the draw tube eyepiece holder.
An Auto-Collimater is the second mirror, with a hole in the center and one to the side so it gets complicated to explain but imagine standing between two mirrors and looking to either side and only seeing one image, you.
If either mirror is off then you'll see a million you's like in a fun house mirror set up.
Now bouncing the reflection back & forth requires the a third mirror in the path to turn the reflection 90° out to the eyepiece in the end of the draw tube, where the Auto-Collimater now is placed.
So the third mirror needs to be accurately tilted and rotated to center the reflections path, that's your secondary mirror.
So now we eliminate the "You" standing there and to see an image stack on both mirrors of a center spot of your primary we put a third mirror with a hole in it so you can see the center spot image, as you tweek either of the main mirrors involved that stack will shift to a set of center spots, as you adjust the mirrors to see only one spot you're collimated.
That's what an Auto-Collimater does, it's the third mirror with a hole in it.
So when I go out and set up for viewing, first I adjust or tweek my secondary so the laser dot hits the primary mirror center spot, then I set my Barlow into the eyepiece holder then the laser, I adjust the primary so I see the reflection of the ceter spot pretty well centered on the screen, I remove the Barlow & laser and drop in the AC, now I tweek just a bit more and I have a stack of center spots,,,,,, about 5min if I take my time.
All the laser has to do is be accurately aligned to is to be able to illuminate the center spot on your primary mirror thru a Barlow.
When you drop the laser into a Barlow it defrac's the beam into a wider beam,
I hope this helps explain why I'm not too worried about collimating my laser, even tho I spent a great deal of time doing it I learned that I didn't need to, but the lesson learned was well worth the time.
Here's a link to Catseye, go there and read.
All the credit for what I know about it goes to many that have helped me here on CN.