To use this module, the company must have access rights for multiple
currencies.

Follow these steps to use manual currency:

1.  Go to Invoicing \> Create new invoice/bills.
2.  If you need to change the currency to one other than the company's
    default currency, you will see an option for 'Manual Currency'.
3.  Check the 'Manual Currency' box to enable manual currency entry.
4.  Specify the desired currency rate for the selected currency.