The shortest way is to go straight from Wenchang Road, which is the road between Normal University and Polytechnic University. It takes about 7 minutes to walk. There is a gap near the wall of the University of Technology on the right. From there, turn left at the basketball court and walk straight for 6 minutes. Now it's time to swipe your card and take a shower.
Or walk directly from Wenchang Road to the gap next to the bath.