You can either fill a form or go online. If you go the physical way, then there are two forms; the common application form that captures your basic details such as address and bank account details, and a form to start a systematic investment plan (SIP). If you invest in a fund house for the first time, you need to fill the common application form to open your account. And then the SIP form, if you need to start a SIP. Subsequently, if you wish to invest a lumpsum, then you need to fill the ‘additional purchase’ form.
If you go online, you need to first open an account and fill in your details. The portal will determine if you are compliant with the current Know-Your-Customer (KYC) norms.