Aisle prepared by youth leader without difficulty (6)
I believe the answer is:
easily
'without difficulty' is the definition.
(synonyms)
'aisle prepared by youth leader' is the wordplay.
'prepared' is an anagram indicator.
'by' is a charade indicator (letters next to each other).
'youth leader' becomes 'y' (I've seen this in other clues).
'aisle' is an anagram of 'easil'.
'easil'+'y'='EASILY'
(Other definitions for easily that I've seen before include "Effortlessly" , "Very probably" , "Without difficulty or effort" , "no problem!" , "Simply" .)