Dominate Human

Overview
To successfully charm a target for conversion to a Servants, you must first reduce their health below 30%, activate, and channel Kiss of the Vampire (default key R) and dominate the target. While channeling, the target can still attack you. Once a target is dominated/charmed you will need to escort them back to your base (they can be killed by other enemies or projectiles) and place them in an empty Servant Coffin and spending 100 Blood Essence. The conversion process will take ~2hours in real time. If you have charmed a target you do not wish to convert, you can release them by holding down the Release Target ability which replaces Kiss of the Vampire upon capturing a target.

While using Dominating Presence, your equipped spells will be replaced with either Kiss of the Vampire (if you have not charmed a human) or Release Target (if you have charmed a human), meaning you are unable to use any of these skills. However. you will still be able to use your ultimate ability and travel ability. If you have a charmed human, you are unable to shapeshift to a different form, but you are able to ride a horse.

V Blood bosses are not able to be dominated.

Strategy
It is best to clear out nearby enemies prior to charming a target. This is to ensure that you will not be interrupted while channeling this ability, and will also have an easier time escorting your charmed human back to your base. It will also be good idea to bring along a Horse, in order to reduce the amount of travelling time.