If you have to register or change the mobile number in your PAN card, for that you will have to fill the PAN card correction form, this can be done from the PAN center, if you have the knowledge of filling the online form, you can go to the website of NSDL or UTI. SW PAN correction can be done, for this you will have to pay 107 rupees almost charge online, if you want to check the full process then you visit mypancenter.com website, it provides training related to PAN card.