I had loads of old towels and like ray of light took donations of old towels from mil, sil etc to stockpile.
I had a mattress protector on my bed-good job too as I was in bed when my waters went-but that's the only think I had. No plastic sheeting/shower curtains here!
I also had oil burner, to burn lavender and clary sage oil as they really go well together plus lavender helps to relax you and clary sage can help speed labour up, and candles. It was amazing being in a completely candle lit room!
Straws are a god send (make sure they're bendy) as they mean you can drink no matter what position you're in!
We made sure house was tidy and clean but only to our usual standard, we didn't go ott.
I also had old duvets, duvet covers and pillows as I change position loads in labour and they were useful when I wanted to sit/lean though I spent the majority of my labour stood up and walking!
We had an angled lamp ready as well as midwife advised us to get one or a torch so they can see afterwards if any stitches are needed.
I also played music during labour. I chose classical pieces and my natal hypnotherapy music.