How must I drop or replace a ball, and what if I get it wrong?

Dropping (Rule 14.3): drop the ball yourself, from knee height, so it falls straight down without touching you or your equipment before it hits the ground. A ball dropped the wrong way must be dropped again with no penalty, as long as you have not played it. If you play a ball dropped the wrong way, it is one penalty stroke if played from the relief area, or the general penalty if played from outside it or if the ball was placed instead of dropped.

Replacing (Rule 14.2): replace the original ball on its original spot by hand and let go so it stays there. Replacing it the wrong way on the right spot is one penalty stroke. Playing it from the wrong place is the general penalty, as is failing to re-create a lie you altered in sand.

Marking and cleaning (Rule 14.1): before lifting a ball that must be replaced, mark its spot with a ball-marker or a club. Failing to mark, marking incorrectly, or playing with the marker still in place is one penalty stroke. Cleaning a ball when the Rules do not allow it is one penalty stroke.

Wrong place (Rule 14.7a): the general penalty (two strokes in stroke play). Under Rule 14.7b, a serious breach not corrected before the next hole begins means disqualification.