If going somewhere new...
I passage plan on the PC, load it onto the chip, and print out the route (passage/route plan).
Put chip into GPS188C, and refer to that when driving about.
I carry the charts as backup (used with passage plan mentioned previously), and have both a fixed and handhelp compass on board.
If just playing out doing RIB-Rides etc in the bay...
I usually go from one feature to another (channel markers, SWB, etc) and go places that I know - but I do have some waypoints marked as 'get me back' references if something happens or if viz dissappears rapidly. I've also got the route back into the harbour from the various channel markers/bouys onboard the RIB (and in my head now), together with a spare pair of undies should both viz and the GPS go at the same time......
D...