I’d echo the above I think. Keep filler items (noodles, rice, chips, crap sarnies, etc.) to a minimum, you want to fill up on the tasty stuff instead.
I, perhaps controversially, always have a smaller plate first time round to get a feel for the food, work out what is good and what is not. I also think that you tend to get a restocking of food so if you time your second visit to coincide with this you get a fresh stock of the stuff that you liked from the first visit.
Finally, make sure you pick your beverages correctly. This is not the places for fizzy pints of lager as they will take up valuable stomach space, this is the place for shorts, ideally with a flat mixer.