1.) Some sort of Wrap. I have a Moby and I LOVE it. Emma has been pretty fussy and in about 2 minutes after she's in the wrap she's asleep. It also helps me get stuff done while I'm chasing around my almost 2 year old.
2.) Colic Calm.. Soothes tummies within minutes and makes hiccups go away. I think angels start singing after listening to an hour of screaming that stops instantly :).
3.) Desitin - Best diaper rash cream I've found. Enough said.
4.) A great diaper bag. I've found that this is so important, especially with 2 little ones. You have to be organized when you go out or else you'll just be frustrated and not be able to give all of your attention to your babies. I use the Cindy Tote and I LOVE it. I also use the thermal tote to bring snacks/bottles/sippies etc. Go here to get one!
Hope this helps you new mamas!