form_submit_zapier_hook.js

$('.form_class').submit(function( event ) {
    var form = $('<form></form>');
    form.attr("method", "post");
    form.attr("action", "test.com");
  	var email = $( "#id_of_field_for_email" ).val();
    var first_name = $( "#id_of_field_for_first_name" ).val();
 	form.append("<input type='hidden' name='email' value=" + email + "></input>");
    form.append("<input type='hidden' name='first_name' value=" + first_name + "></input>");
    var formData = $(form).serialize();
    // Make AJAX request
    $.post("https://hooks.zapier.com/hooks/catch/1234567/abcd01e/", formData).complete(function() {
    });	
});