Here's a link to the Washington Flyer website, which includes a bus schedule: http://www.washfly.com/coach.html At the West Falls Church Metro station, get on an Orange line train going towards Metro Center station in downtown DC. At Metro Center station, change to a Red line train going to Union Station. Get off at Union Station and walk three blocks to the Greyhound Bus station, which is located at 1005 1st St, NE. To get there you would go out the front of Union Station and turn right onto 1st Street, walking along it about three blocks. Be aware that the area is a bit desolate--definitely don't do it at night. Here's a link to the Metro website: http://www.wmata.com
There is an information desk at departures, they can help and give you all the information you need.
hope this info helps
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