"Whatever you do, thou shalt not break the seven deadly sins of mothers' group."

OK, you’re finally feeling confident enough to leave the house with your new baby, and seriously craving some adult conversation.

But joining a mothers’ group can be like going on a blind date. Get it right and you’ll have the time of your life. Get it wrong, and all you’ve got is a bunch of tired, hormonal women making awkward conversation about sippy cups.

So what’s the secret to success? Thou shalt not break the Seven Deadly Sins of Mothers’ Group…

Sin #1: Judging.

Just because you share a postcode and a vaguely similar ovulation cycle with these women, doesn’t mean you’re going to share all your values.

Everyone thinks their version of parenting is right, however, there’s a fine line between being passionate about your beliefs and getting into troll territory. Going all Judgy McJudgeface probably isn’t going to change their mind about sleep training/disposable nappies /teaching their baby circus tricks, or whatever it is you’re at odds over.

When people get defensive, things can escalate, and I’ve witnessed some all-out brawls about the most ridiculous subjects (I mean, who cares that much about nappy brands?). You don’t have to avoid the tricky topics, but keep it polite and know to simply agree to disagree.

Sin #2: Being scared to overshare.

Oversharing isn’t just allowed, it’s expected. In fact, you haven’t had the true mothers' group experience until someone shows you a photo of their child’s poo (I really, really wish I was joking).

From baby bodily fluids to detailed labour stories, relationship woes to emotional ups and downs, the full rollercoaster of parental experience will be laid out – whether you’re into it or not.

Seriously, though, this is probably the one place you can say whatever’s on your mind, knowing that at least one other person will be going through the same thing.

You may feel embarrassed or uncomfortably exposed, but think of it as free therapy with good advice and a coffee on the side.

Sin #3: Sticking to your tribe.

Surrounding yourself with like-minded supporters is definitely a good thing, but finding your tribe doesn’t mean you have to stick to it.

Just because you might love your designer active wear, and she might be more of a socks-with-Crocs kind of a gal, don’t assume you’ll have no common ground as mums.  In my experience, the most genius advice and the most sympathetic ears can come from the most unlikely of places. After all, babies are babies, whatever you’re wearing (they’ll just vomit on it regardless).

Sin #4: Complacency.

In any group, you have the organisers and the just-going-along-for-the-ride types. That’s fine in the real world, but when you’re talking about 20-odd women who have more hormones than a Russian Olympic team and only had about 12 hours’ sleep between them... well, let’s just say not everyone’s thinking clearly.

I know someone whose entire group simply phased out because they took a break over Christmas, then no one bothered to kick off the catch-ups for the new year. Sad, huh? Make regular plans, keep it simple and casual, and if your What’s App has gone suspiciously silent for a while, don’t be afraid to get things rolling again.

Sin #5: Modesty.

Mothers' goup may be a place to trade war stories, but remember to celebrate the triumphs, too. Too often, new mums get caught up in trying to outdo each other in the disaster stakes that they’re afraid to share when things are going well.

Yes, people may be jealous... but they’ll also really, really want to know how you did it. So baby slept through the night? Sing it from the rooftops! Worked out how to calm a screamer down in less than 10 seconds? Patent it! Hopefully one of your tips can help make someone else’s mum life that little bit easier.

LISTEN: Psychologist Kirsten Bouse speaks about why some women can't stand Mother's Group, and others find it to be a saving grace (post continues after audio...)

Sin #6: Gluttony.

As in, not enough of it! Gluttony may be one of the actual Seven Deadly Sins, but that kind of talk ain’t got any place at mothers' group. Put any self-loathing talk of ‘post-baby bodies’ away, eat the damn brownie and enjoy.

Sin #7: Taking it all too seriously.

The first year of parenthood is guaranteed to be one of the hardest of your life. Being responsible for the safety and wellbeing of a tiny human (and doing it all on minimal sleep) can be scary at best, and utterly overwhelming at worst.

While mothers' group is the place to vent, cry and seek advice, it’s also meant to be fun. Take a moment to laugh, share those embarrassing stories and even – shock, horror – do something that’s not about the baby.

After all, it’s probably the biggest event on your social calendar for the week, so you may as well make the most of it, right?

Chloe Flynn is a Sydney-based TV producer, writer and mother of two. Her first novel Group is out now. Visit Amazon for more.