Carol to get a true understanding of what Scrooge was like before he was visited by the three ghosts.

Looking at the first stave, then, we see that Scrooge is a miserly person who does not enjoy the company of others. To convey this idea, Dickens uses hyperbole, a form of figurative language, to describe Scrooge. This is shown in the following line:

"Scrooge! A squeezing, wrenching, grasping, scraping, clutching, covetous old sinner!"

He also uses similes, like "solitary as an oyster" and "sharp as flint." You may wish to use similar methods to describe Scrooge's dislike of others and his desire to be separate from the rest of society. 

Secondly, Scrooge hates Christmas, as we see in the conversation he has with his nephew, Fred. Dickens uses dark humor to demonstrate Scrooge's attitude: he thinks people who enjoy Christmas, for example, should be buried with a "stake of holly" through the heart. Fred cannot understand this attitude, since he views Christmas as an opportunity to nurture family and friendships. You may wish to use some dark humour in your poem to describe Scrooge's "bah, humbug" attitude or highlight the contrast between Scrooge and Fred by comparing their visions of Christmas.

Finally, Scrooge hates charity and believes that poor people are the cause of their own misery. When talking to the charity collectors, for instance, Scrooge's sentences are heavy with alliteration, as you can see in the following line:

"I don't make merry myself at Christmas and I can't afford to make idle people merry."

By repeating the m sound, Dickens really drives home the point that Scrooge does not want to help the poor. You might use a similar sound repetition to achieve the same effect.