She travels to a different cathedral around the UK and celebrates by giving commemorative Maundy coins to a select group of citizens. Typically, these are chosen by the age of the monarch. For instance, this year she is 83, therefore 83 men & 83 women will be chosen by the officials of the cathedral (in this year, Bury St. Edmunds, Suffolk) and they will each receive 10p in Maundy coins. After the official ceremony, I don't know what she does.