WPdonations: Editing Submit Donation Form Fields

gistfile1.php

// Add your own function to filter the fields
add_filter( 'submit_donation_form_fields', 'custom_submit_donation_form_fields' );

// This is your function which takes the fields, modifies them, and returns them
// You can see the fields which can be changed in: includes/forms/class-wpdonations-form-submit-donation.php
function custom_submit_donation_form_fields( $fields ) {

    // Here we target one of the donation fields (donation_amount) and change it's label
    $fields['donation']['donation_amount']['label'] = "Custom Label";

    // And return the modified fields
    return $fields;
}