The 23-year-old joined the Blues in August 2015, but was loaned out to German outfit Schalke 04 for regular action last campaign after playing 15 league games in his first season at Stamford Bridge.
Back in training following a long injury layoff, uncertainty hangs over where the fullback will be playing next season amid talks of a return to Schalke.
"He still has to continue to train hard and must be strong," Njitap told Ghana Soccernet on the sidelines of the ongoing FIFPro Division Africa Congress in Accra.
"Many footballers coil in their career when things don't go well.
"But instead of keeping his chin down, he must keep it up and continue to work hard to wait for his opportunity and make good use of it.
"When the chance comes, he must try to do what he does better, play football and try to play well."
While Premier League side Everton have also expressed interest in Baba, there is still a possibility he will stay at Chelsea this season, with reports that manager Antonio Conte wants to give the former Augsburg man a chance to prove his mettle during preseason.
He made 13 league appearances involving 7 starts for Schalke before being knocked out by injury last season.
Cameroon star Njitap played for Chelsea between 2003 and 2007.