O'Mahony leads a youthful looking team and the Munster flanker is Ireland's youngest captain since Brian O'Driscoll led the side in Australia in 2002.
But O'Mahony does not believe it will change how he performs on the pitch.
"There are a couple of more things before the game and you go up for the coin toss but it certainly doesn't change the way I play," he told the Irish Independent.
"It is a bit different, there are certain things that you have to do differently. You have to do what you normally do on the pitch, I won't be carrying myself any differently, you just do what you normally do and try and look after the lads.
"It's a huge honour for me and my family. I was delighted to get the call and delighted for Besty as well.
"It's an exciting time for the squad, there's a blend of young players and experience, so it should be interesting."