You feed a Christmas cake with 1-2 tablespoons of liquid of your choice; be it brandy, sherry, or fruit juice, every two weeks in the run-up to Christmas.
To feed the cake, simply uncover the top of the cake (leave the sides wrapped to stop it from drying out) and poke the cake surface several times with a skewer. Spoon over the liquid making sure the whole cake is evenly covered.
If you like your Christmas cake to be extra boozy, you could go for 3-4 tablespoons at each feeding instead but don't overdo it otherwise your cake will be super soggy come serving time.
Cover the cake back over and set a reminder on your phone or write on your calendar to feed again in two weeks' time.