You may want to deposit money into an expense account if you add cash into the cash float or petty cash drawer, or make a payment into a credit card account.
To make a deposit into an expense account, you can either click on 'Expenses' from the quick navigation menu, or you can click on 'My Business' then on 'Expenses':
Where your expense accounts are listed, click on the 'Deposit Funds' button:
Once you have typed in the amount you want to deposit, and specified the account you want to allocate these funds to click on 'Add Deposit'. You can add a note to this deposit if you wish, but this is optional.
The deposit amount will be added to the account balance and reflect in the list of expense accounts.