Given a form the plugin will find all the fields and store their associated text using jQuery's .data() method.
This means it requires inputs to have an 'id' and an associated label using the 'for' attribute, e.g.
<form action="#" method="post">
<label for="example">Example Label</label>
<input type="text" id="example" />
</form>
It can then be initiated like this:
$('form').inFieldLabels();
The method also accepts a filter parameter in case you want to limit the in-field labels to specific elements or :not(specific elements):
$('form').inFieldLabels('.in-field-label');
More documentation can be found here