Few simple steps that work every time.
Find a suitable spot, acceptable depth, and good as possible seabed type, away from any other anchored boats.
Stop the boat over it and drop the anchor, deploy the chain while drifting back being careful not to drop a load of chain on top of the anchor.
When you've let out sufficient scope secure the anchor chain on deck.
Now leave it for a few minutes while the anchor takes its initial set.
Motor slowly astern until the chain straightens out.
Watch the chain carefully as you increase engine revs to spot any signs of the chain jumping, indicating a dragging anchor.
Take a look around you and find a spot to be used as a fixpoint to indicate the movement of the boat if any.
Increase engine revs further to at least 1,800 RPM.
Dragging? if you have enough space at the stern, motor slowly backward to give it another chance to set, no room? Retrieve the anchor and start the whole process again.