All you have to do is fund your Trading Account. Your Base Pack gets enabled automatically in SMP once you fund your Trading Account or SMP. You need to ensure that you have opted for Base Pack (Infinite Trading Plans) for the segments you intend doing Zero Brokerage trading at the time submitting your KYC.
If you have not opted for a Base Pack at the time of Account opening you need to email email@example.com to activate your the Base Pack else you will be charged at default brokerage rates. Click here to check the default brokerage rates.