Making forms accessible isn’t something hard to do, but most times, it gets overlooked as developers pay more attention to parts that get noticed by users who can see visual changes. But then again, there are users out there who rely on assistive technologies and accessible forms help them tremendously in completing their tasks without unnecessary hitches.
There would be times you would want to offer your users an indication of the current form element they are on. A simple, non intrusive manner for this would be as simple as changing the background of the element using CSS. Users who are using their keyboard to move through the form elements would also benefit from this as this provides a more obvious cursor position.