Unless you're searching in an urban area, ALWAYS check a topo map before you go. That will tell you what the terrain surrounding the cache is like.
If, on the map, you don't cross any lines going from the parking area to the cache, it's all flat. The more lines you cross, the greater the change in elevation. If you come to a bunch of lines that are *very* close together, that's a steep incline, possibly a cliff.
Remember what Korzbyski said - "The map is not the territory."
The most important tip? If you're not having fun, try something different.