G&P. A lot of it comes during the planning process. I usually walk with my wife and I like to explain to her what is coming up has we go along. It gives her confidence I know what I am doing and I can prepare her for the "sticky" bits. This usually breaks down to relatively few points which hang together to describe the bulk on the route.
For example from our last walk:
Walk down from the car park through a line of trees to meet a probably muddy track and turn left.
Follow this track generally E with a sharp downhill S at one point then E in the woods looking for a better track going SW.
Follow better track generally downhill curving SE in wood.
Before next turn wood finishes first on left, then on right then cattle grid. Hard right onto really good track, possibly metalled.
Go gently uphill past cabin camp to car park, turn main track left to cross stream on track
Track, probably not as good, climbs steadily in woods, take hairpin right to climb with drop on right.
At end, track drops to meet another track. Climb W through wood, leave through gate, keep climbing to road and car park.
Right at end of car park uphill to trig point.
Pass trig point to meet EW track, go E to start.
Harder to write here than to remember in the planning stage as I can relate each bit to the shape of the route in my head and the broad elevation profile (sequence of major ups and downs). The important points are the major turns.