If you file as married filing separately and you do not live in a community property state, you enter only your own W-2. If you live in a community property state you must report half of your wages and half of your spouse's wages. Form 8958 will be included in your tax return to show how you calculated the wages.
The community property states are Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin.
Alaska, Tennessee, and South Dakota have elective community property. I don't know how that works. If you live in one of those states, and no one posts any additional information here, you should consult a local tax professional.
