How to validate user input on a jotform?

I am using one of your template contact us form for my website. I would like a way to validate users input into this form. Say for instance a user doesn't type in their last name, I want the form to come back and tell the user "Please type your "Last Name".

Thank you for contacting us.

It is possible to set a field into a Required mode, so that the form will add the validation to the particular field.

This is how it will look like on the form.

The error state validation can be also styled via the Form Designer.

Unfortunately, you can not set the specific validation message for each field, since we have a lot of different input types and they work differently.

Please feel free to contact us if you need any further assistance.