As a mom of five wee beasties, let me tell you...lol, just kidding. Honestly, despite the fact that after 5 I may have some idea what I'm doing, people still give me advice. One memorable lady was very, very upset that I didn't have a sweater on my baby. It was July and if I could have successfully worn the onsie outfit, I would have. And this is my advice: They put them in dumpsters and they live. Your kid will be fine.
I do tell childless/free friends that I did my best parenting before I had kids, too. And in defense of moms everywhere...if you breastfeed - cool. IF you don't - cool. And just because I personally make babyfood, it does not mean that I am a nut. It is less expensive & takes about 20 minutes a week. I also make my own laundry detergent. If your budget allows you to buy these products, well you rock on with that. As long as your getting the job done, it makes no earthly difference as far as I can tell. Oh, and disposable vs. cloth....either way, your little one is going to poop on it.
Just quietly I have a internal giggle to myself when I hear some yet to be mums announce how they're going to do this and how they're going to do that. Best laid plans and all that..... I'd never outright say it to a stranger to cause offence though. As mums we just do the best we can do, never let another parent tell you otherwise, I guarantee you they made many mistakes they just won't tell you. Mum's will ask you stuff knowing they won't like the answer and then they'll chastise you because it makes them feel powerful and validates their daydream of being the perfect parent. Never let anyone make you feel like a piece of crap.
Answers to unsolicited questions you don't want to answer: "I haven't really thought about it, we'll decide when the time comes" "not really sure at this stage" "I have no idea" "I'm sure baby will help us decide what we will do"
ETA: Oh and if some kind person decides to share their horrible birthing story with you prior to birth a simple "shut up" is acceptable IMO. I just don't get why people do that. Nasty!