The 38-year old, who was named as player of the season in both campaigns so far since moving to Worcester, said he was shocked when coach Gary Gold asked him to take charge.
O’Callaghan, speaking at the launch of the Aviva Premiership in Twickenham, said he intends to make the most of the captaincy as he prepares for another season of combat.
“I was honoured by it, I really was. I was flattered by it when he asked me. But the way I’m looking at it is that I need to give the leg-up to younger guys around me. Many of the younger lads have leadership qualities but it’s as if they don’t really know it themselves.
“I have been around good leaders, guys who knew what they are doing and they helped me develop. I now want to try do that for the young lands coming through with Worcester.
“Back with Munster, nobody would have seen Denis Leamy as a leader outside the group, but when he spoke in our squad everyone listened.
“Rog (Ronan O’Gara) once said that Leamy was the sort of guy who spoke for three minutes but what he said lasted for three months.
“That was a lovely thing to say, but it was so true.
“I want to help the young lads in their development, that’s exactly where I am in my career and I know how influential an older player can be, like Jim Williams was for me in Munster. It’s the small things but they add up.
“I remember going into team meetings and I didn’t have a notepad and Jimmy said to me that I wasn’t good enough that I did not have to take notes at a meeting.
“He made me think about rugby all the time, how to prepare, prevent injury and so on.
“I was afraid of him when I was young but now I am so grateful to him,” said the 94-times capped international.
O’Callaghan, of course, will have another ageless former Munster player to assist him in the first half of the season after Peter Stringer joined on a short-term contract to the end of the year.
By then the former Irish scrum-half will be 40 but O’Callaghan said that Stringer has lost none of his combativeness.
“I suppose you should be careful what you wish for. The Boss is back, no doubt about that. Straight away, it’s as if he has been with us for four or five years. I love playing with him, the things that Strings does, but it comes at a cost and he bosses you.
“The other day, he stamped on my hand in training because I didn’t place the ball right but these are the little things that Strings does and it quickly brings people into line. I’m delighted he is with us,” added O’Callaghan, speaking before he led Warriors out for the first time against his native Munster.
It has become an annual preseason fixture at this stage but O’Callaghan hates playing against the Reds.
“I don’t like it, I find it unbelievably tough. All I ever wanted to do growing up was to play for Munster and I always find it hard to play against them and I’ll be glad when the game is over.
“I suppose it’s all about respect. I never knew the value of Simon Easterby playing with him for Ireland until I played against him. When you were playing with him, you were wondering what he was up to but when you played against him you realised he was involved in everything and he earned your respect.
“And I’d love that with those Munster boys, that they would come off the field thinking Donners is decent.”