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There are different ways to achieve this, but one common procedure is:

1. Retrieve the form and the submit button using their respective HTML element IDs or class names in JavaScript.
2. Attach an event listener to the form or its individual input fields that listens for changes in their values, such as oninput or onchange.
3. In the event listener function, check if all the required fields are empty or null, or if they only contain whitespace characters. You can do this using logical operators, array methods, or regular expressions, depending on your preference and the complexity of the validation criteria.
4. If any of the fields fail the validation, disable the submit button by setting its disabled attribute to true, or its CSS class to a disabled state that prevents interactions, such as using opacity or pointer-events. You may also give visual feedback to the user, such as changing the color or text of the submit button, or displaying an error message.
5. If all the fields pass the validation, enable the submit button if it was previously disabled, or leave it enabled if it was already enabled. This step is optional but ensures a better user experience and accessibility, as it allows users to submit the form as soon as they finish filling it out correctly.