I'm back with money for betting slips (8)
I believe the answer is:
mistakes
'slips' is the definition.
('mistake' can be a synonym of 'slip')
'i'm back with money for' is the wordplay.
'back' says the letters should be written in reverse.
'with' means one lot of letters go next to another.
'money for' becomes 'stakes' (I can't explain this - if you can you should give a lot more credence to this answer).
'im' in reverse letter order is 'mi'.
'mi'+'stakes'='MISTAKES'
'betting' is the link.
This may not be right. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for mistakes that I've seen before include "Errors" , "Misguided or wrong acts" , "Blunders, slips" .)