Prepare a full pint of Guinness using the two-part pour method (pour 2/3 of the pint tilting the glass at a 45 degree angle before letting it sit and settle for 2 minutes - once it has settled, dip the tap in the foam and finish pouring the pint held straight - let it settle again for 1 minute before serving).

Once it has settled add 1 shot of Black Currant Schnapps (or Syrup for a non-alcoholic addition) to the pint. If you are a fairly experienced bartender, you can pour from the bottle and actually "draw" a shamrock shape in the foam.