off trail site gives others space and reduces impact on trail
flat site with mild convexity for natural drainage if it rains
in the breeze to reduce bugs but not too exposed
avoid bottom of valleys or dry creek beds where air is coldest and risk of flooding in heavy rains
avoid topography likely to become wind tunnels
avoid hilltops where exposed to storms and lightning risk
avoid under large branches which may drop without warning
avoid being next to lightning targets (and if lightning is possible, avoid open spaces too)
avoid being near habitat paths
avoid cliff faces with hazard of rock falls or in the snow, avalanches
choose dry ground as it is warmer and you will have less condensation
granite or gravel is usually good
if possible select a site with a natural windbreak
ensure your site is not going to allow a large pool of water under your tent - choose well drained higher ground
AVOID need for digging trenches - these should not be needed with modern tents with floors and conflict with Leave No Trace principles