Naemenson:

Its not so much a poem as an anecdote. you start with some sort of plausible reason for discarding the scotch (past its sellby date or whatever) then you go through the repitition becoming more visibly drunken with each repetition

so:

I opened up the first bottle, thought I had better try it so I had a glass, then I threw the rest away down the sink

I opened up the nex bo'le, Had a glass(hic) and threw the rest away down the, down the ...sink

about bottle 5 its:

I oped...opend the next glass, thought I better try... , drank a sink and poured it down a bottle (hic)

Ultimately the reciter is clearly smashed out of their brain and still trying to go through the repitition. you can end by either collapsing or quitting the stage to the accompaniement of violent retching. It's all in the way you tell it, if you can have a correspondingly deteriorating repeated sequence of opening, drinking and pouring which is at odds to the words it helps