Try to eat protein, high-fiber foods, and complex carbohydrates that will stay with you during the day.
Avoid salty and fried food, which can make you thirsty (e.g. fries, samosas, etc.).
Avoid sugary stuff for suhoor, because it can cause your blood sugar to fluctuate.
Take plenty of liquids and also be careful to drink enough after iftar and during the night to replenish the liquids you have lost. Being dehydrated can make a person dizzy.
Many people find that a cup or two of plain yogurt at Sehri time reduces thirst, as well as hunger, during the day.