Moving IMac to new location

Shutdown and unplug it.

Pack it in the original box if you have that.

If you do not have the box, wrap it with padding or bubble wrap.

If possible, move it inside of your personal vehicle instead of the back of a truck or moving van.

Treat it like any delicate bit of kit for which you paid a fair bit of money. Shut it down, box it up, transport it with care, put it on a desk and start it up.

Some of us even keep the original box, but others might see that as obsessive.