Buy cotton wool balls and use with water instead of buying wipes as they're expensive!
Buy nappies on special in advance, but not too many as baby grows out of them fast.
Buy New baby clothes on eBay. I got heaps for .99c cause people bought them new and didn't use them!
Most importantly, take your PPL/ baby bonus paperwork to Medicare NOT crntrelink as you get the money faster. I got mine in under 2 weeks!