Van Gaal has taken the reins at Old Trafford after guiding Netherlands to third place in the World Cup in Brazil.
The experienced Dutchman is putting the United squad through their paces on a pre-season tour to the United States and England striker Rooney is determined to make an impression on the 62-year-old.
Rooney is quoted as saying in The Sun: "We all have to go out and show what we can do,
"We have to show him every day in training what different qualities we have got as players and a team.
"Everyone wants to impress the new manager so that is what we are all aiming to do.
"We will try to put what we are doing in training into the games. Obviously, we have a manager with new ideas so we have to try to train well and make sure we are listening to what he wants to do and take that on to the pitch. We have to show him what we can do.
"I've only had one session but the preparation has been really good. I'm just looking forward to getting more sessions in before our first game."
United take on LA Galaxy in their first game of the tour on Wednesday.
