Pouring as one’s tying up (7)
I believe the answer is:
lashing
'tying up' is the definition.
'lashing' can be an answer for 'tying' (lashing is a kind of tying). I'm not certain of the 'up' bit.
'pouring as one's' is the wordplay.
I cannot quite see how this works, but
'as' could be 'in' (I've seen this in other clues) and 'in' is present in the answer.
'one's' could be 'as' (a thing is one thing) and 'as' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for lashing that I've seen is " punishment by cat?".)