Labour tips: -
My tip re. gas and air is if you've been using it for several hours, it can make you shake really violently and feel really cold so make sure you've got a blanket or something else to keep you warm, and take socks with you for the same reason.
If you can't use a birth pool but think you may want a bath, take some blu-tack to block up the overflow so you can fill the bath up more!!
I found aromatherapy and a good mix of mellow music helped me relax in the early stages - worth preparing a 'mix' of your favourites in advance!!
Rescue remedy is supposed to help keep your spirits up (I forgot to use mine so can't say whether it works or not) and arnica tablets are supposed to help with healing.
If you're staying in hospital take plenty of magazines / other stuff to read as it's really boring once baby's asleep if you can't sleep yourself.
Will post more when I think of things!!!
LBxx