Head to this month's payroll review screen.

Select "Change pay date" from the Actions dropdown (pictured below)

Head to your payroll settings

Update the Pay Schedule to the date of your choosing. In most cases this will take effect from next month. Go to this month's payroll review screen to check .

If you want to update this month's payroll as well follow the instructions in the "Change your payday as a one-off" section above.