Why do you think George asks Lennie to familiarize himself with the location of the clearing where they spend the night?

If the reader finishes the novella, Of Mice and
Men by John Steinbeck, and then returns to the first chapter and rereads it,
he/she will apprehend that almost everything that happens in the plot is laid out in
this first chapter.  This pattern of Steinbeck's metaphorically reflects the line of
Robert Burns's poem, "To a Mouse," whose line the novella's title has
borrowed:

The
best laid scemes of Mice and Men, gang aft agley

[The best
laid plans of Mice and Men often go
awry]

George lays the best
plans he can--as does the author, Steinbeck--, conditioning Lennie to return to the
brush by the river if anything "bad" happens, but like the mouse who builds its nest in
the field that is mowed in Burns's poem, the "nest" of George and Lennie's dream is
destroyed in the death of the figurative "mouse" in Lennie's bear paws, Curley's wife,
that Lennie inadvertently, like the mower, kills.  With the dream of George and Lennie
destroyed, there is no real safe "nest" to return to:  indeed, "the best laid plans go
awry."