First of all, you will need to choose the correct blue
to indicate water. This should not be too watery.
You must remember: people do not like wet feet.
If there is no water to indicate, no matter,
you must still elect a blue. Let me recommend
eggshell, at a push azure. Choose a symbol
for church/temple/mosque/synagogue. Choose
a symbol for pub. Dedicate your life
to the twin and warring gods of Precision
and Wild Abandon. People do not like
to be lost. Buy Mandelbrot's 1967 paper
on the coastline paradox, put it on the highest shelf -
but buy a stepladder. Take a little licence with rivers,
especially their curves and estuaries. Add
an oxbow lake if at all possible. If the area you
are mapping has no sea/lakes/rivers/streams,
I have to question why you are bothering. You
won't get to use that lovely blue you spent so long
deciding upon. Do the Norfolk fens instead. Better
yet, East Anglia in its future state, quite utterly
submerged like a sodden Constable. Come on,
get your coat, I'll show you. You won't need your shoes.