Go to finance 

Select Banking 

Click Payment for the relevant bank account 

Click on add payment 

Enter the date of the payment 

Select the supplier name 

Select the type of payment 

Debit code defaults to "Trade Creditors". Only change this to “Creditors Loan Account” if you have no unpaid supplier invoice to apply the payment against.

Enter the amount to be paid 

Add in the comment 

Click on the applied column next to supplier invoices that the payment relates to. 

Click add payment