Number the entire book in the head without a drink (8)
I believe the answer is:
paginate
'number the entire book' is the definition.
'paginate' can be an answer for 'number' (paginating is a kind of numbering). I am unsure of the 'the entire book' bit.
'head without a drink' is the wordplay.
'head' becomes 'pate' (humorous term for the head).
'without' means one lot of letters goes inside another ('without' can be similar in meaning to 'outside').
'a drink' becomes 'gina' (I can't explain this - if you can you should believe this answer much more).
'pate' going around 'gina' is 'PAGINATE'.
'in the' acts as a link.
Can you help me to learn more?
(Other definitions for paginate that I've seen before include "Order and number the sequence of a manuscript" , "Number pages (in book)" , "To plan layout" .)