The best way to improve your TOEFL score is to so much practice! Taking TOEFL Network’s high-quality TOEFL sample practices, teaching materials & sample questions are just some of the many ways you can become more positive speaking, listening, writing & hopefully even thinking in English!

Since the sentence should be "How can you improve your TOEFL score?" I think another provider should also be under consideration.

Fun quiz. Translate "The best way to improve your TOEFL score is to so much practice! " into England.