You will need to know the names of all the Tudor Monarchs and who they married. You will need to know what each monarch's religion was and what the main events of their reign were; making a nickname up about them, which links to each fact, may help you remember. Additionally you will need to know what a catholic and protestant is and be able to describe terms like provenance, Reformation, Monastery and Dissolution.
To go for GD look at target 59; find out a little more about the the situation in Europe (who was Martin Luther?) and what life was like for ordinary people in England.