1) Click 'Payment Options' under the 'Commerce' heading of the Control Panel.

2) Under the 'Offline Bank Transfer' heading, edit your 'Offline Bank Transfer' settings.

3) When you are finished, scroll down & click the 'Save' button.

Updated
1) Click 'Payment Options' under the 'Commerce' heading of the Control Panel.
2) Under the 'Offline Bank Transfer' heading, edit your 'Offline Bank Transfer' settings.
3) When you are finished, scroll down & click the 'Save' button.