clearing credit card in full each month / partial payments?

[planteria]

in terms of a credit file showing consistent 'borrow & repay' and therefore helping to build up a positive credit history, is it important to clear a full monthly Amex balance by DD, or would it be just as positive to spend, leave the DD for the full balance in place, but also make payments to the account during the month? -the latter would suit me fine accounting-wise.