For the shuttle run, the only thing that improved my time was practicing proper technique. During the run, keep yourself low so that it takes less time to touch the ground. Stay low, and start turning a few feet before you reach the line. By the time you touch the line you should almost be completely turned around, which will save you time. Make sure you perform the shuttle run in good shoes as well. I practiced on the road in front of my house, but the road is hard to grip. A basketball court is the ideal place to practice.
For the basketball throw, grasp the ball with your hand and bring the ball to your wrist. Hold the ball steady between your hand and wrist, which creates a sort of "cupped" hold on the ball. "Stand" completely straight-up when you're ready to throw. Bend backwards and twist your body simultaneously so that you "wind back" like a catapult. When you go to release and throw, thrust forward and torque your hips. Use your body's momentum rather than just your arm to throw the ball. Again, practice is key. Just keep practicing and finding methods that allow you to throw the ball far.
Good luck