How should i act this part out?

Lady Macbeth is plotting the death of King Duncan. She knows that her husband isn't the kind of guy to go around killing his kin to become king so is trying to figure out how to get him to "man-up" and do it. The rest of the speech is actually her talking about how if she weren't a women, she would just do the deed herself.

The Raven himself is hoarse-- Shakespeare frequently uses the raven to represent evil. When you are reading the line, think "The devil has spoken"

That croaks the fatal entrance of Duncan from under my battlements.-- A battlement is an external wall of a castle that soldiers used to protection while firing on their enemy. The term"under the battlements" means to be under fire. Duncan is walking into a trap and is going to die.

Unsex me here and fill me crown to toe with direst cruelty,-- women are suppose to be sweet and gentle. She is saying "screw being all soft, I am head to toe BAD MoFo"

Stop up the Access and Passage of remorse- I'm not going to feel bad about what I'm going to do

So that no compunctious visitings of nature,- even though it would be natural to feel bad about it

shake fell my purpose, -- deter me from my evil plan

nor keep peace between the effect and it! and don't let it remorse prevent my plan from happening.

So that last sentence is saying "I'm not going to let remorse (which most people would feel) stop me from doing what I want and I don't want remorse to stop my husband from doing it either"

I would read those lines like I was an evil step mother in a Disney movie. :)