Pre-heat your oven to 180°c (160°c for fan-assisted ovens or Gas Mark 3-4) and line a couple of baking sheets with grease-proof paper.
In a large bowl, cream the butter/margarine and sugar together. Sift the flour in the flour and bring together to create a dough - you may need to use your hands.
Roll on a floured surface with a rolling pin, until around 0.5-1cm thickness & cut with a round cutter. Transfer your biscuits to your pre-lined tray.
Bake for around10 minutes until they are very lightly golden. Baking time will vary depending on the size of your biscuits. Transfer to a wire cooling rack & ensure they are completely cool before decorating.