To add "Hedwig's Theme" in your Nokia cellphone than what you have to do is the following:

Step 1: Click on your Menu tab
Step 2: Select Tones
Step 3: Select Composer
Step 4: Enter in the notes below:

Version 1:
Tempo=45
16b2 8e3 16g3 8e3 16b3 8.a3 8.#f3 8e3 16g3 8d3 16f3 4.b2 16b2 8e3 16g3 8e3 16b3 8d4 16#c4 8c4 16#g3 8c4 16b3 8#f3 16g3 4.e3 16g3 8b3 16g3 8b3 16g3 8c4 16b3 8#a3 16#f3 8g3 16b3 8#a2 16b2 4.b3 16g3 8b3 16g3 8b3 16g3 8d4 16#c4 8c4 16#g3 8c4 16b3 8#f3 16g3 4.e3

Version 2:
Tempo=125
8.c2, 16#d2, 8d2, 4c2, 8g2, 4.f2, 4.d2, 8.c2, 16#d2, 8d2, 4b1, 8#c2, 4g1, 4-, 8g1, 8.c2, 16#d2, 8d2, 4c2, 8g2, 4#a2, 8a2, 4#g2, 8e2, 8.#g2, 16g2, 4#f2, 8-, 8#d2, 4.c2, 4-, 8g1
or
2- 8- 8b1 8.e2 16g2 8#f2 4e2 8b2 4.a2 4.#f2 8.e2 16g2 8#f2 4d2 8f2 2b1 8- 8b1 8.e2 16g2 8#f2 4e2 8b2 4d3 8#c3 4c3 8#g2 8.c3 16b2 8#a2 4#f2 8g2 2e2 8- 8g2 4b2 8g2 4b2 8g2 4c3 8b2 4#a2 8#f2 8.g2 16b2 8#a2 4#a1 8b1 2b2 8-

Step 5: Select it as your ringtone
Step 6: Test it out