Sometimes motivating people is not easy. Most people get motivated by different things. You can try to motivate people with positive feedback on their work, you might try a friendly competition, because many people are competitive. You may try setting a certain goal and the first one to reach it gets a prize. Get to know your employees and you will figure out ways to motivate each and everyone of them, because you will figure out what drives them to succeed and you can customize your motivation techniques.