IMPS is a way to transfer money like UPI, NEFT, etc. IMPS is instant, i.e, the money is credited to your account instantly. The service is available all the time, 24 hours a day, even on bank holidays.
The first step is to add your bank account details in the slice app. Once your bank account details are verified, you can take cash directly into your bank account. The verification happens instantly most of the time. In some rare cases, bank account verification may take up to 48 hours.