Okay, So I'm about to start working the "evil" night shifts...with twins...Oh sh*t...
I've heard lots and lots about things I should and shouldn't do.

>DON'T miss out on sleep (quite an obvious one really)
> Have a small nap a few hours before your shift
> When you do sleep ensure you have something like Porridge before you go bed...and avoid eating heavy meals on shift...(it'll put your body to sleep)
> Eat Hobnobs(Yes this advice was given by an actual Nurse...which made me snigger slightly, but supposedly due to it's content of concentrated carbs, it'll keep me going longer during the night and also have a good amount of sugar to keep me buzzing )

Any other advice that you've heard, that I might not know...anyone have any experience? that could help me more than guesswork

You could reset your Circadian rhythm, though doing this frequently is probably very unhealthy.
The body has a pre-programmed 'morning' as the first time it eats in a long time. So if you don't eat for a while (I think it's 16+ hours) and then eat, this will become your new morning.

So if you make your morning later in the day, then you'll be able to stay up later.
I'm no expert though, so it might be worth looking into.