So the best advice I got was to refer to it as birth preferences rather than plan, as pp says they rarely go to plan.
Mine certainly didn't. I wanted a water birth, active labour, very little involvement from medical staff, but in hypnobirthing, and absolutely no way to forceps.
Had merconium in waters so not pool, had to have constant ctg monitoring for the same reason, ended up in theatre with forceps. (Though I must admit I was. Or stressed one bit, and well looked after, forceps were absolutely fine, healed perfectly, no lasting damage or pain), baby came out beautifully with perfect shaped head haha.
However, the other things I included such as I wanted a dark room, my husband to be with me at all times and that he could vouch for me, to use and be encouraged to use hypnobirthing techniques, to avoid opiate pain relief was all listened to. The midwives even said when I arrived on ward they had dimmed the lights as per my request etc. The midwife knew to ensure I had skin to skin and delayed cord clamping in theatre and this was respected, as was my request for husband to be with me when/if they had to site an epidural as I'm a massive needle phobic, also that hubby was to announce the gender. All of that I'd forgotten about. It because it was written down, the midwife vouched for it and made clear that's what would happen and it did. Also the vitamin k injection.
When I was back on ward post delivery the obstetrician came down to see how I was recovering as it was a traumatic birth (didn't feel that way to me, hormones are an amazing thing, I was in cloud 9) and that the birth was exactly the opposite of my birth plan, he wanted to apologise for me not being able to have the birth I wanted and wanted to check I was ok. I thought that was really considerate and showed they had read the preferences.
So mine was a page of bullet points under subheadings
Intro: our names and jobs (both work for NHS, felt it was only fair to warn them), first baby, previous losses, very anxious mum
Environment: dim room, fairy lights, quiet etc (it wasn't quiet in the end, I kept making jokes as I remembered I find silence uncomfortable)
First stage preferences: ie being encouraged to be active, try different positions, avoid pain relief
Second stage preferences: be in the pool etc, paracetamol etc.
Third stage preferences: can't remember now
Delivery: inc cord cutting preference, skin to skin, delayed clamping, gender reveal, wanting help with breast feeding, placenta management (natural or injection) and vit k injection for baby.
There's tonnes of templates online but they're OTT and Americanised often.
nct I think has some templates on their website