Everyman’s attitude leading to ultimately tedious tricks (10)

'tricks' is the definition.
The answer and definition can be both acts as well as being plural nouns.
Perhaps you can see a link between them that I can't see?

'everyman's attitude leading to ultimately tedious' is the wordplay.
'everyman's' becomes 'I'm' (where the crossword setter is 'Everyman').
'attitude' becomes 'posture' (synonyms).
'leading to' says to put letters next to each other (some letters go before or lead others).
'ultimately' indicates one should take the final letters.
The final letter of 'tedious' is 's'.
'im'+'posture'+'s'='IMPOSTURES'

Can you help me to learn more?