Garage requires GFCI protected outlets. You can put the clamp with fasteners inside, better yet just attach the clamp to the cable first and fish the romex into the panel with the clamp already on it, then just put the lock ring on. For me with all kinds of materials already available, I would use a plastic clamp that can be installed after the romex is already in the box, cable pulls through it and it snaps into the box. Since this is a finished wall, no additional straps, staples, support, etc are needed.

They make plastic NM bushings that are designed to be snapped into the hole from the inside of the panel/box.

Cable is supposed to fastened within 12" of a receptacle box. One staple will be required unless the cable is feeding through a stud which counts as fastening.

"Cable is supposed to fastened within 12" of a receptacle box."

This does not apply to cables fished behind surfaces.
Exposed cables require fastening.

If you use an old work box with drywall clamps the only hole in the drywall needed is to mount the box.

Cut the hole, fish the cable with the connector for the panel already attached into the panel.

Install the lock nut in the panel, then feed the cable into the box device box.

Fasten the box to the drywall and tighten the internal clamp on the cable.

You can even use a regular cable clamp by placing it on the cable if you have box fill issues with the internal cable clamp (same trick as the panel).
You strip the cable jacket long enough to feed into the box opening, slip the box into the wall, pull the cable clamp tight into the box using the wires, then fasten the lock nut.

Are the garage walls finished? - e.g. drywall. If so, you get an exemption from the stapling requirement if you are fishing the line behind a finished surface. If the wall is open, spring for the whole 3 cent staple.

Thanks for all the tips. Yes, my garage walls are finished. If they weren't and there was no drywall, this would be a no-brainer job.

One other question I have is about fastening the cable at the box. I will be using an Old Work box to attach to the drywall. Is there a clamp in/on that box for clamping the Romex? I thought the romex just runs into the box via a hole and then screws onto the outlet?

The plastic/ fiberglass boxes have their own clamp and nothing else is needed. Make sure your outlet is a GFCI outlet.

"The plastic/ fiberglass boxes have their own clamp and nothing else is needed."

The "clamp" is the little tab in the cable entry hole.
It bands over when the cable is fed and grabs the jacket, preventing the cable form being pulled back out (somewhat).

What will these outlets be used for?

Hey Spencer, I like the idea of putting the clamp on the wire and then pulling it through, I try to think out of the box but I never thought of that.

Yeah, I like the idea of putting the clamp on the wire first as well. I never though of that!!

These outlets will be used for yard equipment... i.e. Electric Mower, Electric Blower, Electric Weed Whacker, etc. Whenever I have a couple of them going (I get help to do my yardwork!) and then someone clicks the garage opener, my circuit breaker trips. So I thought I'd install some dedicated circuits. Yes, I know to install GFCIs.

Does this sound ok?