If we've discussed extra bits and pieces for your order, this is the place to add the extra payment.
Just add the amount required, available in multiples of 50p or £1, i.e. to pay £7, select 7 of the £1.
Don't forget to add a note at checkout to remind us what you're paying for.
Please don't add extras before asking if its possible. Simply adding a quid and saying 'send me an extra pot' is not an option.