Jokes about youth leader in right clothes for a special occasion (4,4)
I believe the answer is:
glad rags
'clothes for a special occasion' is the definition.
(I've seen this before)
'jokes about youth leader in right' is the wordplay.
'jokes' becomes 'gags' (gag can mean a joke).
'about' means one lot of letters goes inside another.
'youth' becomes 'lad' (lad means a young man).
'leader in' indicates taking the first letters.
The first letter of 'right' is 'r'.
'lad'+'r'='ladr'
'gags' placed around 'ladr' is 'GLAD RAGS'.
(Other definitions for glad rags that I've seen before include "Fancy clothes for laggards" , "Best clothes worn for special occasions" , "Best bib and tucker" , "Special kit" , "best suit" .)