Flexibility and a willingness to try will get you more calls from the temporary service. You can never tell when the next career opportunity may appear. Be ready to work. Take care of any obstacles to your employment before you make yourself available, including transportation, day care arrangements and personal appointments. Consistently being on time shows that you enjoy what you're doing and desire to continue.
Questions show an interest in getting the job done right.
Try different settings. Use temporary employment to try out different environments, different companies. It's less stressful than an interview, and you can also determine if you really want to work there. If you liked an assignment, ask to be requested the next time they need someone. Between assignments, call your temp service regularly.