Sure, even beginners hit on things that can be helpful.
I need to go back and look at all the responses again, but.......what i have been doing so far is to use a piece of white cardboard, down pretty low, so it is like looking at a copy of the print. That way i know where to hold the Slit/Hole for burning. Not "Hold".....but move around.
I have never tried using that swing-out, deep red filter for setting up the burn.
In case it hasn't already been spelled out the distance above the paper has two effects, for this example consider an opaque disc between the lens and paper:
increased height increases the size of the shadow on the paper
increased height causes the blur at the edge of the shadow of the disc to be wider so that the transition from dark to light is spread over a greater distance
my experience is that variation of the height of the mask above the paper is one of the fundamental adjustments in dodging and burning and is something that with trial and error and practice becomes a spontaneous skill.
I use hands and card board masks - which ever works best. To make a very exact mask, I generally rest a sheet of cardboard on a couple of old film canisters to allow fine tracing of the image.
Them is fighting words!.
I probably agree with this advice to those who are starting out.
But after a few decades of this, I find hands to be the best choice.
I've used hands, arms, and my head once...accidentally. I also use cutouts, red painted, or penciled mylar, SCIMs... whatever is appropriate for the job. With tools that are suspended above the paper, I wiggle them and move up and down slightly. If you don't a halo from the dodge tool or handle with show up in the print.