Taming your hamster requires patience and time. Where you get your pet from often maps out the level of taming your hamster will need, as good breeders will start handling the babies at a young age, whereas pet shops often don't have the time or concern in taming their livestock. The species of hamster will also affect the taming process; while Syrian hamsters tend to be easier to tame due to their size, smaller species may take longer as they are smaller and more speedy.
Until your hamster is tamed I wouldn't suggest you kept them in a cage with a lot of hidey holes or tunnels, as they can become a refuge for the hamster and this makes cleaning very difficult; it also makes it very difficult to get near your pet. With children you should always supervise handling and educate them on how to hold the hamster, encourage them to keep the hamster low incase of an accident (which could injure your pet and push the taming process right back).
How To Start The Taming Process
1) Remove the lid of the cage, offer your pet a treat to encourage the behaviour. Have a suitable carrier ready such as an empty food storage box or your hamster ball. 2) Gently encourage them to go inside the container and offer them another treat, this will show them there is nothing bad happening and that they get food for this behaviour. 3) Allow your hamster to climb out onto your lap, gently cup your hands to scoop them up and continue to offer treats as reinforcement (or bribery). Make a tunnel with your hands and let your hamster run through them.
You can also use a playpen or bath enviroment to get close to your pet, however they should always be supervised as hamsters as agile pets and will escape pretty quickly.