Assuming you mean emotion rather than sensation? One thing I like to use is to think of the physical sensations and actions associated with emotions. Fear sends a chill across someone's skin or makes their hands shake. Lust makes someone flush and feel hot. Etc. Describe those, and you often won't need to name the emotion--if I say "Andrew went pale and slumped back in the chair as if he couldn't hold himself upright." in response to some news, then the news was clearly a shock.