Take off your glasses: they are not allowed unless you include a signed doctor's note.
White or off-white background, neutral expression, eyes open and mouth closed.
Print on matte or glossy photo paper; the photo must be from the last 6 months.
How to do it with Requisito Listo
Open the «US passport photo 2 × 2 in» template in the app.
Take the photo with the on-screen guide (or pick one from your gallery).
The app centers your face, makes the background white and gets the exact size and file weight.
Check the checklist, then upload or save it.
At the end you'll see a checklist: size, file weight, background and format. If something doesn't comply, it tells you what to fix before the portal rejects it.