Before preparing the cage you should consider where you are going to place the cage. The cage should be placed away from direct sunlight, away from draughts and in a room of constant temperature. Avoid putting the cage near a heater where the hamster may become hot and be sure to put the cage out of the way of any other pets which may harm your hamster.
Fill the water bottle with water and fix it to the cage at a height that the hamster will be able to reach comfortably. Check by running your finger over the end of the spout that it is delivering water. If it is not give the bottle a little squeeze, dry the end of the spout and run your finger over it again. Pet Shops sell liquid vitamins which can be added to the water and these can be particularly beneficial if your hamster is ill.
If you are using a food dish fill it with hamster food and place this in the cage, otherwise sprinkle some on the floor of the cage.