How can I get from Pingyao to Bejing by bus?

There is no direct long-distance bus that runs between these two places.
You need to reach Taiyuan by train first. If there is bullet train from Taiyuan to Beijing, you can take one.
If not, you can go to Taiyuan General Bus Station, close to Taiyuan Railway Station. There are some coaches that can take you to Beijing.
The bus schedules are 08:30, 10:30, 12:30, 14:30, 16:30 and 18:30.