Bring a girl up to be a credit to you (5)
I believe the answer is:
asset
'credit to you' is the definition.
I can't tell whether this defines the answer.
'bring a girl up to be a' is the wordplay.
'bring a girl' becomes 'tess' (I can't explain this - if you can you should give a lot more credence to this answer).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'to' means one lot of letters go next to another (I've seen this in other clues).
'tess' in reverse letter order is 'sset'.
'sset' put after 'a' is 'ASSET'.
Can you help me to learn more?
(Other definitions for asset that I've seen before include "Tessa (anag)" , "Something that's worth having" , "Item of property" , "Advantage, strength" , "Anything considered valuable" .)