Hiddink suffered his first loss of his second spell in interim control last Tuesday at Paris St Germain and goes into Sunday's FA Cup fifth round against Manchester City seeking a victory to extend his 100 per cent record in the competition.
The Dutchman won the trophy in 2009 after Chelsea beat Watford, Coventry, Arsenal and, at Wembley in the final, Everton.
Chelsea won the Premier League and Capital One Cup last season, but their astonishing fall and the departure of Jose Mourinho in mid-December led to Hiddink being called upon to restore stability for a second time.
"Deep down you must play with joy," Hiddink said.
"If you play with joy then the best comes out of a player
Joy is not always laughing
It is enjoying being a professional, enjoying training and doing your job, which is sometimes tough.
"But if you enjoy it and if you do it, not all day smiling, but you feel a little bit natural, then I think the performance is unconditioned."
Hiddink did not wish to comment on Mourinho's methods, but his approach seems to have paid off, with the loss in Paris the first defeat since the Portuguese's final game in charge, at Leicester.
"They came out of a very difficult situation in the last half year, we cannot deny that," Hiddink added.
"I did not want to note too much about the past, I wanted to go in the way to get the best out of the team, which is the way we did it.
"Relaxed is when you (cross) your arms, the sun comes and you have your pina colada
That is relaxed.
"This is not relaxed
This is trying to get the best out of the players
One player, you have to embrace
Another player you have to pinch a bit.
"Everyone has his different approach, to get the best out of them, then add it to the team performance."
Chelsea and City meet in the FA Cup for the third time in four seasons.
Manuel Pellegrini's side won the previous two, beating the holders in the 2013 semi-final and winning a fifth round tie at the Etihad in 2014.
Source : PA
Source: PA