Book ahead. Flights tend to be a lot cheaper if you book in advance, so if you have a fixed travel itinerary, take advantage of this fact by booking online as far ahead of the travel date as possible.
Cook your own. Save money on expensive cafes and restaurants by staying in self service apartments. By cooking your own food, you can eat well and save money too, which is great news if you have a fixed meal allowance, as you can keep the money you save for more important things.