Through appointment of clergy in royal courts and replacing Anglo-Saxon earls with the Normans.
Explanation:
King Henry II of England expand the monarchy’s power by more efficient tax collection. King Henry II claimed the right to try clergy in royal courts, and unified the system of royal justice. William the Conqueror changed the aristocracy and nobility of England by replacing Anglo-Saxon earls with the Normans who fought with him side by side in the war. This established a new Norman Elite, which threatened the Anglo-Saxon population which was now ruled by Normans. This decision of him make him more powerful and control over the its people.