If you come up 880, stay left as you cross oakland and follow
the signs to 80. Be careful after you come across the flyway to bear
right to Sacramento (East).
Take University east till it hits the west edge of campus.
Turn left on Oxford.
Turn right at Hearst (the northwest corner of campus).
Continue up the hill past the signal. Soda Hall is the green building on your left. "You can't miss it." There is meter parking on the street.
(official directions: http://www.eecs.berkeley.edu:80/Campus/Directions/#soda)