What works for me:
lots of carbohydrates (wholewheat preferably), more fresh fruit and vegetables, more protein (fresh meat/chicken, not processed crap)
more water throughout the day, sip constantly, don't try and drink 10l at once
avoid salty or sugary processed crap
have your biggest meal of the day at breakfast time, next biggest at lunch and the last meal/2 meals should be snack sized so you don't go to bed on a full stomach
try and have 4-5 smaller meals a day rather than 2-3 large meals