The ground and VL pins power the logic section that must match the voltage swing of the controlling signals. Unused controls can be tied either to ground of to VL.
V+ and V= power the switches, themselves, and those rails must contain all analog signals passing through the switches. VL and Ground must be inside the V- to V+ range.
The unused switch connections (COM, NO, NC) may be left floating or tied to any voltage between V- and V+.