My advice is a bit pathetic I feel but it did work for me - I had to practice to get it right, my first births were fraught and scary - my final birth I took control of, I made decisions all the way through the end of my pg about how it would work and I told all the people hat mattered what those were.
The decisions I took were these... I wuld not be hurried, I would not be pushed, I would not panic. Sounds silly? In practical application what it meant was this, I was confident that no-one would do anything withot my say so, everyone knew that, if I could not answer right now, they were to wait until I could. All involved knew my ideal and also knew that I was happy to change if I felt it was required.
I planned out what I hoped would happen, I planned contingencies where I could (eg Csection, monitoring etc) and then I stopped planning. Once I was confident everyone was on the same page as me I refused to worry any more.
When I was in labour I was able to divert myself onto other things, I took rescue remedy in water (a lot) and then thought about the other dc, I rang my mother and chattted about her meal out... and hung up when I felt like it, confident that sh would know why...
I guess what I am trying to say id this... I envisaged my labour as I wanted it, I dealt with any forseable issues that may have come up and then i told everyone I could think of what I had decided and simply expected them to fall into line. I did not waste time or energy wondering what if X objects to Y I made it plain that this was about me and nothing else would suffice.
My birth was simple, almost easy and pain free - not really pain free but the pain that I could deal with, it never got scary or out of control.
The biggest thing for me was deciding where to have my child, for me I felt most in control at home - being at home was a huge step. For you it may be a different place, don't worry about where it will be jsut give thought to it, if you feel hospital would be best for you make that happen, equally a MW unit and so on.
I may be wrong but I feel strongly the most scary thing about pain is feeling out of control, being in pain but being in control makes it all much easier to deal with. Take control!
Everyones experience is different but you have to know that none of them are wrong, if you awant drugs ask for them without fear, if you want ice ask for it, if g&a makes you sick don't use it. Move around, stay still, swear, scream, be silent as fits you best. It is only when you try to fit in to someone elses ideals or vision that things start to be wrong IMHO!