Ringo Starr occasionally playing on good material (9)
I believe the answer is:
grosgrain
'material' is the definition.
(grosgrain is a kind of material)
'ringo starr occasionally playing on good' is the wordplay.
'occasionally' means one should take alternating letters (letters taken at regular intervals or occasions).
'playing' is an anagram indicator.
'on' is an insertion indicator (as in clothing 'on' a person).
'good' becomes 'g' (abbreviation).
The alternating letters of 'starr' are 'sar'.
'ringo'+'sar'='ringosar'
'ringosar' is an anagram of 'grosrain'.
'grosrain' enclosing 'g' is 'GROSGRAIN'.
(Other definitions for grosgrain that I've seen before include "Fabric" , "material" , "silk" , "silky stuff" .)