Well to start off with for me, contractions were bearable. I put my TENS machine on as soon as they started, which I think helped. I tried to sleep, but kept waking up every 15 minutes.
I then had contractions all the following day, but I was at home so I could eat, watch TV, get on the birthing ball etc. I remember thinking that the pain was ok - not unbearable. By that night at about 11pm I was exhausted - couldn't get to sleep because of the pain, and the labour ward told me to go and have a warm bath as my cervix probably wasn't even dilated at all yet.
At 2am I decided to take myself down to the hospital (when I say that, I mean, I did not wait for them to tell me it was ok!), and I was 5-6cm dilated. By this point I was in a lot of pain due to the contractions coming closer together (no rest period) and really was very tired after having no sleep for two nights. An hour later, I said that I needed to push (no-one believed me), but she checked and I was fully dilated. Pushed for 1.5 hours and then out he came. At crowning, it was very sore and actually felt as if someone had cracked my pelvis in half, however I am sure this is not the case for everyone. I did have a 2nd degree and a labial tear though so I'm sure that would account for some of the agony!
The one thing which would have helped for me is if I had been able to get some sleep at some point - I was literally so exhausted that I couldn't focus on pushing.
The thing is OP, it is so different for everyone - I had a friend who only started to feel real pain as she was fully dilated.
I am pregnant again now so trying not to think about it all too much!!
I think it's good if you can keep an open mind - I was all set for a water birth, but I needed continual foetal monitoring so I couldn't.
Also, if you can find a really good antenatal teacher it will really help you to be prepared.
Hope it all goes well for you when it happens!