Yes, you should always make sure to warm up before exercising.
Make sure to choose an exercise that uses your total body to get all of your muscles warmed up. You don’t ever want to stretch cold muscles, so choose dynamic (moving) stretches, such as arm and leg circles.
After you workout, you want to bring your heart rate down slowly, and the stretch out your muscles. This is when you do static (holding) stretches. Make sure to hold them for about 30 seconds each.