Using attributes to help users to enter the data:
<form method="post">
<label for="number">Card number</label>
<input id="number" name="number" autocomplete="cc-number" inputmode="numeric" required>
<label for="name">Name on card</label>
<input id="name" name="name" autocomplete="cc-name" required>
<label for="exp">Expiry date</label>
<input id="exp" name="exp" autocomplete="cc-exp" required>
<label for="csc">Security code</label>
<input id="csc" name="csc" autocomplete="cc-csc" inputmode="numeric" required>
<button>Complete payment</button>
</form>