The Dutchman is taking over from Jurgen Klopp, who has left the club after more than eight years in charge.
While Westerveld knows that losing such a legendary manager will have an impact, he has been impressed with former Feyenoord coach Slot’s teams in the past.
He stated on LFCTV's Extra Time: "The minute I heard Arne's name (linked), I was like, 'Yeah, that's actually a perfect fit.'
"Over the years people talk about Arne in Holland and they always compared him with Pep Guardiola and Jürgen Klopp.
"He always showed Liverpool clips during training sessions and analyzing games. He was showing Liverpool clips on how to play. He's playing in a similar style. It's been well-documented how he plays, what he wants in a team.
"Apart from that, he's also a genuine nice guy. He's always in for a joke, which is really important because it gives a sort of balance in the team, in the group – focus, train hard, have a laugh when you can. Take the pressure off certain situations but never lose the focus on winning games.
"It's easy to motivate the first XI but if you talk about the players that are on the bench, 12 to 25, they're all happy with him as well in all the clubs he's trained, so that's really important and says enough as well."