Costa has picked up four yellow cards in Chelsea's first six league games of the 2016-17 season, and while the Spain international came through unscathed in the victory over Hull City, it leaves him walking a tight rope against the champions on Saturday afternoon (15 October).
Another yellow will see him handed an automatic one-match ban, with Chelsea's next game the return of Jose Mourinho to Stamford Bridge on Sunday 23 October.
While Conte insists he doesn't want to see Costa shy away from his natural instincts on the pitch, he admits the former Atletico Madrid has been reminded what is at stake and what the consequences will be if he steps out of line.
"We know the situation," Conte told a press conference on Friday. "Diego knows the situation. It was the same before the Hull game. We must think to the present, and not look forward.
"Tomorrow he must fight in the same way he did in the previous games. I hope he pays attention and doesn't get another yellow."
Costa has enjoyed a superb start to life under the Italian coach, scoring six goals so far this season to make him the Premier League's leading scorer.
That form has kept Michy Batshuayi out of the first-team. The Belgium international is yet to start a league game following his summer arrival from Marseille, but with a suspension looming over Costa, Conte took the opportunity to praise the 23-year-old.
"I think that Michy is a young player, but he has great potential," he said. "On the technical aspect he can grow a lot to become a fantastic player for Chelsea."