Dongsi 8 Hotel to Tsinghua university

How to get to TSinghua University from Dongsi Super 8 Hotel ?
Riding a taxi is quite expensive as I am on budget trip. What's the easier & cheaper way to Tsinghua university?

How to get to Beijing Dongsi Super 8 Hotel from Beijing airport?
Hello! I am arriving at Beijing (PEK) around 10:00 PM. Riding a taxi is quite expensive as I am on budget trip. What's the best but safe way to get to the Dongsi hotel?

Hotel address: No.137 Dongsiwutiao, Dongcheng District, Beijing, China
Area: Dongcheng, Dongzhimen/Workers' Stadium
Overview: The hotel is located in the Dongsi business, culture and tourist area.

Thanks in advance.
Thanks in advance.