CARL GLASSMAN / TRIBECA TRIB

With three babies in attendance at last month's New Dad's Boot Camp, fathers-to-be got to change more than one diaper.

"We need a diaper change. Who’s up for it?” Tim Mulvaney asked, laying his 3-month-old daughter, Nava, on the rug and waiting for volunteers.

A couple of expectant fathers got down on the floor with him while nearby Bruce Razza and his 8-month-old  daughter, Ainsley, were ready to take on two other student fathers.

Then the questions to the “veteran” dads came flying as diapers gingerly came off.

“It’s okay that I’m kind of forceful, even though she’s not happy?” one expectant father inquired as he worked with a crying, squirming subject.

“How do I tell which side is the front side?” asked another, puzzling over the tiny diaper in his hands.

“How many times a day does she us­ually go number two?” a third wanted to know.

This is New Dad Boot Camp, a three-­hour class that each month brings together a different set of fathers-to-be and new fathers they can learn from.

Spon­sored by the NYC Dads Group and held at Tribeca Parenting, 46 Warren St., the course is part hands-on, part support group.

“In the beginning it was really tough emotionally for me. I had a lot of guilt, like I didn’t have a helpful role,” Darrin Cirillo, father of 6-month-old Mia, told the group last month. “But once I talked to other dads and understood what I was feeling was normal, I felt a lot better about it. I started to pick up other things that I could do.”

CARL GLASSMAN / TRIBECA TRIB

Tyler Rann gets practice holding a baby with Darrin Cirillo's Mia.

Matt Schneider, co-founder of NYC Dads Group and facilitator of the workshops, said it’s important to build parental confidence in fathers from the start.

“So often mothers feel like they’re the only ones who know how to take care of their baby,” Schneider said. “We want to make sure that fathers don’t get pushed out in those early weeks.”

For Tyler Rann, whose baby was due in a few weeks, that confidence seemed to come as soon as Cirillo put little Mia comfortably into his arms.

“Yeah, chillin’ out, I like it,” Rann said proudly. “I have this touch with women. It’s been known to happen.”

Seated in a circle, the dads and dads-to-be talked about post-partum blues and intrusive in-laws, baby calming and swaddling.

“Any of the dads have an idea of why babies might cry?” Schneider asked, as he held up a white board and marker. “They don’t love you?” one of the men offered.

The men spoke easily with one another about their insecurities and even marital stresses that come with a newborn.

“There are certain topics you don’t want to bring up with women,” said expectant dad Rob Callahan. “As a guy, maybe you’re more willing to be vulnerable in front of other guys and say what’s on your mind.”

And as for changing his first diaper?

“It’s not as terrible as I thought,” he said. “It helps to get one under the belt.”

The next New Dad Boot Camp in Tribeca takes place on Jan. 28. For more information go to nycdadsgroup.com.