WARNING: This page is about a different car, the 2010 BMW X6, 2009 BMW X6, and 2008 BMW X6. However, it is still accessible from the selected car via links, so may be relevant.
Place cylinder head on special tool 11 9 000
.
Press valve spring down on spring retainer with special tools 11 0 009
and 11 9 017
.
Fig 1: Identifying Special Tools 11 0 009 And 11 9 017