Go to GST portal – www.gst.gov.in
Obtain a 15-digit GSTIN (GST identification number) which will be issued based on your state code and PAN.
Upload the relevant invoices on the software or the GST portal. An invoice reference no. against each invoice will be allotted to you.
Once all the invoices, inward, outward return and cumulative monthly return are uploaded, check all the errors and file the returns.
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