Manage cracking egg on its head with type of rock (6)
I believe the answer is:
grunge
'rock' is the definition.
(I've seen this before)
'manage cracking egg on' is the wordplay.
'manage' becomes 'run' (both can mean to organise).
'cracking' indicates anagramming the letters.
'on' means one lot of letters goes inside another (as in clothing 'on' a person).
'egg' anagrammed gives 'gge'.
'run' put within 'gge' is 'GRUNGE'.
'its head with type of' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for grunge that I've seen before include "in lazy fashion" , "Grime; rock music style" , "Dirt; rock style" , "Rubbish" , "Thrift-shop fashion" .)