The Scot has guided the Baggies to eighth place in the table with what has been their best start to a Premier League campaign.
"The gaffer has been great. He just tells it how it is and the lads appreciate that," Foster told the club's official website.
"He doesn't sugarcoat things or try and con you, he just tells it how it is. We've got an experienced team and if he was trying to con you then you wouldn't buy it."
Foster and his teammates are back in action on Monday when they host Southampton in the league.