WARNING: This page is about a different car, the 2008 Suzuki Swift +, 2008 Pontiac Wave, and 2008 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: View of Booster Housing Seal and Master Cylinder
Courtesy of GENERAL MOTORS CORP.
Mount the vacuum hose, DOHC engine connection shown, and make sure the connections are tight on each end.