I think if you can identify what it is you are scared of, it's easier to address. So, if you're scared of the pain, have a look at what's available to lessen pain and what's available to manage pain and which options you think you might be interested in. I think knowledge is power tbh. Often, it's fear of the unknown.
The other thing which I think is hands down the most important part of attitude towards childbirth is an open mind. If you have an absolute idea of what you want to happen and see the other options as a negative, then of course you will be riddled with negative thoughts. More so if you then need any kind of intervention or things don't go to script and you'll feel negative during and afterwards. There is nothing, but nothing wrong with having hopes for what you want whether that is a water birth or a cs under ga and there are ways of trying to tip the scales in your favour depending upon your preferences. However, knowing that it's mostly down to luck and knowing what might happen in each circumstance means you can feel in control, knowledgeable and positive about the choices you can make within the labour and delivery you end up having.
Quite often you see threads where people talk about wanting to hear positive stories of childbirth and what they mean is can you tell me about positive stories of natural childbirth. If I type the bare facts of my delivery with dd for example (31hrs of labour, 8hrs second stage, ventouse, manual rotation, emergency caesarean), there will be some people who say they don't want to hear that, it's a 'horror story'. But what if I tell you it's not? It's the story of a baby who was very stuck and the brilliance of modern medicine saw her born healthy with a healthy mother to love her. What if I tell you that I laughed my way into the theatre during my second emergency caesarean and smiled throughout and felt nothing but joy and positivity?
There are things you can't control. You won't know what will happen on the day. You can be armed with knowledge, an open mind and a supportive birth partner and these are the things which create positivity.
Hypnobirthing, meditation etc can be brilliant too.
Mumsnet will help. If you have a question somebody will have the answer or have experienced the same thing.