Need help with client-side form validation

I turn to you with a request for help. I’m facing a little problem with a contact form. I wrote some JavaScript code to handle client-side validation, but how can I make the user see the errors under each field?

Here’s the code:

It seems like the textarea input doesn’t have the necessary id attribute yet. Also if you want to display the custom error message, you need disable the input’s required attribute (by considering the implication), and make sure that the JSFiddle environment is set to use jQuery as the js framework.