This method can be made to work but the necessary air sealing details are demanding and fussy.
How to insulate a single story attic.
Cut a hole in the insulation wherever there is electrical wiring.
There are two ways to insulate triangular attics behind kneewalls.
A better approach is to insulate the roof slope above the attic.
Press and tuck the edges of each part of the blanket to make sure they fit snugly and that there are no gaps between.
To build a catwalk you would usually elevate a section of the framing perhaps with 2x6s installed at 90 degrees to the joists and you would install osb or plywood on top of the elevated framing.
Pull the wiring up through the hole and rest it on top.
If you need regular access to your attic it makes sense to build a catwalk before you insulate the floor of your attic.
The traditional approach is to insulate the kneewall and the attic floor behind the kneewall.
While wearing dust mask and gloves carry r 38 batts of unfaced fiberglass insulation into the attic.