Fly into Sheremetyevo Airport (SVO), the closest airport, located 12.1 mi (19.5 km) from the city centre. If you can't find a flight that works for your travel itinerary, you might consider flying into Moscow (VKO-Vnukovo Intl.), which is 15 mi (24.2 km) away.
You might consider catching a ride on the metro at Oktyabrskoye Pole Station for ease of access to the rest of the city.