When I'm tidy it makes up for shyness (8)
I believe the answer is:
timidity
'up for shyness' is the definition.
'timidity' can be an answer for 'shyness' (I've seen this before). I'm unsure of the 'up for' bit.
'when i'm tidy it makes' is the wordplay.
'when' becomes 'tim' (I am not sure about this - if you are sure you should believe this answer much more).
'i'm' becomes 'i' (I've seen this in other clues).
'it makes' indicates anagramming the letters.
'tidy' with letters rearranged gives 'dity'.
'tim'+'i'+'dity'='TIMIDITY'
Can you help me to learn more?
(Other definitions for timidity that I've seen before include "Fear" , "Lack of assertiveness" , "Diffidence" , "Fearfulness" , "State of being easily alarmed, not bold" .)