My ds is six weeks old, and I've learned so much in the last few weeks. Some things I've realised:
Accept help when it's offered. When ds was 3days old My mum offered to change his nappy, and while she was doing so realised he had a hernia which my dp and I had completely missed in our sleep deprived state. We got it checked out and referred by the hospital the same day. Who knows when we might have noticed it, as it isn't obvious all the time and I would never have known to even look for it.
Ask for help when you need it, don't just battle on. I got mastitis at about day 8, and felt horrendous, and in so much pain, but waited til the midwife came on day 10, to get help. That was 2 days longer I was suffering unnecessarily, she told me off for it and rightly so. I didn't want to bother them but that's what they were there for.
Have muslin cloths everywhere. I have them in basically every room in the house, anywhere I'm likely to sit for more than five seconds has a stash of cloths.
There is no point keeping wipes on a warmer or radiator. As soon as you get the wipe out of the pack it goes cold anyway.
If you have room pop a bouncy seat in your bathroom, to sit baby in for two minutes while you go for a wee/shower. Get a cheap one on Facebook or eBay, and you'll be able to pee without having to hold a squirming baby.
In fact eBay and Facebook marketplace are your friend, when it comes to kitting out for baby. We only bought a couple of things brand new (mattresses, car seat). Everything else came second hand and saved us a fortune.
Finally, Try and find pleasure in the night feeds. I often sit here at 4am with the curtains open watching the sky change colour, or listening to the birds, and just try and enjoy those peaceful moments with my baby, just the two of us. I know it won't last forever, so I'm trying to enjoy it while I can.