If you are a nonresident military spouse living in Virginia only to be with your nonresident service member spouse who is permanently stationed here, the income you earn is exempt from Virginia income tax.
There is nothing to apply for in advance. Leave the exempt income off your Virginia return, and ask your employer to stop withholding Virginia tax. If Virginia tax was withheld, file a return to claim the refund.
Your marriage certificate, your spouse’s orders showing a permanent duty station in Virginia, and proof of your legal residence in another state.