Regardless of your skills or equipment, if you are going to do this shoot, which in my opinion you are not ready for, please please please read up on newborn safety. Many of the images you see from top baby photographers are composites. You have no training, no insurance, and you may very well be risking the safety of these little babies with your ignorance.
+1... No, let's make it +2
I don't think you should take some of the comments you received as offensive or with bad intention, but the complete opposite.
My personal opinion on what makes a professional is different than wikipedia and dictionaries. It seems to me the skill makes a professional, not the money he/she receives. You can do it for the love of it, and that doesn't mean your work will be worst or of lower quality. I really don't think a profession is all about the money.
But anyway, putting all that aside, it might seem like a good idea for you to charge and make some extra money... but the minute you're getting paid for a job, people WILL expect certain quality... and it could happen they'll not like your results, specially if you're just starting on this... so, maybe it's better to gain experience before charging for anything. No matter how great idea it sounds to get a few extra bucks.
It is important to understand that here you have people who's actually been into photography for a very long time, and you can't just say you're charging for a session with 2 months of experience. People will react to this and -most likely- they'll be right.
Anyway, I've never done newborn shots so I can't be of much help... but please take all necessary precautions, make sure to think in advance what different settings you'll be trying... cause you'll be pretty much learning by trial and error as you go through the session.
I'd use manual focus, a fast lens, keep ISO to the lowest possible at all times, wide apertures (smaller f/stops numbers) to isolate the babies from the background and surroundings, and try to use all the natural light possible. If not enough, maybe use an off-camera flash and something to soften the light... although most people will probably say you're definitely gonna need artificial lighting, but of course if depends on the location. Get a grey card and -when possible- use a tripod.
All this being said, I wish you good luck and looking forward to see the results.
Have a nice day!