Williamson has revealed that he has been impressed with the impact of the former England manager due to his approach on the training ground.
He told the club's official website: "This is probably the most tactical work I've done in pre-season for a long time. [McClaren] and his coaches have a lot of ideas, and it is good to learn them and start putting them into practice in the matches.
"It's right up there [as one of the best] because there's a new environment and mentality, which is full of fresh ideas.
"The staff are all striving to create the same environment - a working one in which everyone is focussed on working at a high intensity every day. It's a pleasure to be a part of it."
Newcastle open the Premier League season against Southampton on August 9.