Wow, lots of advice. I will add simply what we do. We have a Rocna anchor.
We line up facing the wind direction.
If we are anchoring in 40' of water then while sitting I lay out about 45' of rode. Not enough to foul the anchor, at least not yet.
Hand signals get my wife to reverse throttle at idle and I lay out 120' or more of rode. Minimum about 3X depth.
I watch the rode and get her to go out of gear and let the boat drift back untill I see the boat slow and the rode lift a bit.
THen back into reverse to snug the chain more for another chain lift only more so.
Then out of gear again so the boat can drift forward and slacken the chain.
THe reverse again but in and out so I jerk the rode minimally.
Then I ask for reverse as soon as the boat start to go forward from the chain weight. THis time She stays in reverse and I look for landmarks to sight on, trees in line, rocks in line, logs stranded in line or close enough in line to be a good sight. Almost always that is enough. Once in a while I need to lay out four time the depth but seldom.
If there is any question about the bottom I will get her to to raise the revs to about 1,000 which is a lot of pull for about 20 sec. If still no movement we shut down and make any further adjustments to rode length for tide changes as needed out to about 4:1 and add the snubber line.
Yes, once in a while I can hear the anchor skating across a rocky bottom. If I cannot find a decent spot without the rock then we move.
Of course I watch that I am not crowding another boat in which case we also move.