Best way is to apply directly to the Mutual Fund company as it will save your 2.25% money as If you apply thru any broker entry load of 2.25% will be cut.
For example, If you invest 1 Lakh into a Mutual fund, 2250 Rs will be deducted straight forward, if you go thru your broker.
Download the mutual fund form in which you want to invest from their website. (Download links provided for all is provided here). Take print out of application form and SIP form. Fill all details, attach a copy of PAN card and cheque and submit the form to nearest CAMS or Karvy investor centre or Mutual fund office. Office locations of CAMS can be found here and for Karvy, it can be found here.
In SIP form, you have to specify your bank details such as account number, branch name, location, MICR code, IFSC code. Auto debit authorisation will be done by Mutual fund itself. It will take 30-40 days for SIP auto-debit to start as first mutual fund house will send the form to your bank. When bank will approve your details, auto-debit will start from your account for SIP.