Be a bit clearer, and refer to rc.conf

src/etc/afs/README

@@ -1,9 +1,13 @@
+# $OpenBSD: README,v 1.3 2003/08/05 14:41:53 hin Exp $
+
 Please enter an AFS cell near you in the ThisCell file.
 
 The SuidCells file specifies cells, other than your home cell, for which
-the AFS client will actually honor the setuid bit.
+the AFS client will honor the setuid bit on binaries.
 
 If you have an "unknown" cell that is not known in the CellServDB, make
-sure to update your cell.
+sure to update CellServDB with your cell information.
+
+afs is enabled by changing 'afs=NO' to 'afs=YES' in /etc/rc.conf
 
 The ARLA project has a webpage at: http://www.stacken.kth.se/projekt/arla/