The former Barcelona and Bayern Munich boss will take charge of his first Premier League game for United tomorrow when they host Swansea (5:30pm).
Though all eyes will be on the Dutchman, Williams isn't concerned by the Van Gaal show.
"We couldn't really have got a bigger game, but the spotlight is obviously with them as they've got a new manager and it's on their ground," Williams said.
"We won't worry about them. We've been working on a system, how we want to play.
Manchester United v Swansea - Premier League Preview
We won't worry about them. We've been working on a system, how we want to play
Ashley Williams
"We need to concentrate on that really and go into the game positive.
"For us, we're just concentrating on ourselves, whoever the opponent is.
"We're aware we're going away to Old Trafford, but I think in these type of games we need to worry about ourselves and what we're doing."
Invalid email
We use your sign-up to provide content in ways you've consented to and to improve our understanding of you. This may include adverts from us and 3rd parties based on our understanding. You can unsubscribe at any time. Read our Privacy Policy