I'll tell you what I hated...I hated when the nurses or even my husband kept rubbing my hair back or my forehead. My sister-in-law was in there with me and she was making jokes...it was hilarious. Honestly everyone is so different but holding my hand so that I could squeeze helped a lot.
You kind of have to play it by ear. I know when I am laboring, I do best when I'm in my own little world, almost trance-like. So if people bust in and distract me, it makes me angry and increases my pain experience. Stay close, observe, and if she is sweating, maybe fan her. Offer ice chips between contractions. Stay quiet if she gets sleepy. Jump in and help support her labor position during the pushing process. Let her know that you won't be offended if she gets short tempered. Tell her to concentrate on what she needs to do and don't worry about you. You are there to worry about her. GL!
To be honest nothing really made mine bearable hehe. I gave birth to a 10lb baby and my epidural didn't work correctly. I had to chase everyone out of the room except my sister because I was so shy about everything. I have to agree with the other poster though that when my sister was messing with my hair it was a nice gesture but it started getting old really quickly. However, It was great when she offered me ice chips. I also had a student nurse in there and it was the first time she got to watch a birth so that kind of made it more exciting for me. She was very kind and probably the best out of all of them, she kept very quiet and she just offered reassurance here and there and she always smiled!