Half-made decision to go up and have cakes decorated (4)
I believe the answer is:
iced
'have cakes decorated' is the definition.
I can't tell whether this definition defines the answer.
'half-made decision to go up' is the wordplay.
'half made' becomes 'de'.
'decision' becomes 'ci' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'to go up' is a reversal indicator (I've seen 'goes up' mean this).
'de'+'ci'='deci'
'deci' back-to-front is 'ICED'.
'and' is the link.
Can you help me to learn more?
(Other definitions for iced that I've seen before include "What cake might be" , "Decorated with sugary mixture" , "Frozen - with a sugary topping" , "found thus in freezer?" , "Dressed in a sweet coat" .)