The Hammers are currently on a seven game unbeaten run in the league but Bilic said there was still room for improvement.
"Our position in the table motivates the players by itself because they are enjoying it and they want to enjoy it longer," Bilic told reporters ahead of Saturday's clash with Watford.
"It has been a good start and we are enjoying it, but keeping our feet on the ground because it is only a start.
"But we are playing well and we are confident. We hope to continue like this because we have good players and a good team spirit.
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"We can improve in transition both ways, we can improve in set pieces, second balls, and we can improve in shooting," he added.
West Ham are unbeaten away from home, having picked up more points on their travels than any other team in the league.
The Hammers had high-profile away victories at Arsenal, Liverpool and Manchester City this season but Bilic said the Hornets are no pushover and his side will have to be at the top of their game to come away with three points.
"It will be a tough game on Saturday because Watford are a hard team to beat. They are also a new team who are improving week by week," Bilic said.
"They look a very organised team, and we have to be on top of our game if we want to continue our good run," he added.
The former Croatia manager said striker Andy Carroll, who scored the winner in Saturday's 2-1 win over champions Chelsea, is capable of more than just scoring with his head.
"When the good balls come into the area where he is it's almost impossible to mark him," Bilic said.
"But his game is not just that. He sees the move two or three steps before."
(Reporting by Shravanth Vijayakumar in Bengaluru; editing by Sudipto Ganguly)
