You can display a summary list of errors at the top of the form in addition to indicating errors on each field. An error summary is especially helpful on long forms, and might include more information than a small error message attached to a field.

<div class="mzp-c-form-errors">
    <ul class="mzp-u-list-styled">
        <li>You must provide an e-mail address.</li>
        <li>You must select a language.</li>
        <li>Your username must be at least six characters.</li>
        <li>You must accept the terms and conditions.</li>
    </ul>
</div>