[header] How to keep hamsters happy [title] Have play sessions with it. [step] You should spend time with it on a daily basis, which prevents your hamster from becoming bored and allows it to bond with you. Swapping the toys in its cage is a good way to freshen up its routine and allow it to participate in different activities. 
You could also place it in its wheel and help push it, encouraging it to exercise. To give it some time out of the cage, gently pick it up and allow it to climb over you, but make sure you are in an enclosed area that prevents it from escaping.