I already know that I will be including a dream sequence within my story later on and it's a crucial part to the plot and being so it's a fairly lengthy piece (at least a quarter of the chapter)
The advice I would like is would you italicize the dream sequence to make it stand out from the rest or not?
If the dream is only a small part of the chapter, sure, it's your style.
If the dream is the entire chapter or is longer than 500 words, don't do it.
You see, italics is used to emphasize the strangeness of something. Like for example, a Spanish term in an English composition. Or a single word that is intentionally put there which is out of place, but is put there to emphasize the weirdness of the situation. Or to imply a different tone, mayhaps even a sarcastic remark in an otherwise, common prose.
When you italicize the whore chapter, it's not longer emphasizing anything. If anything, it makes the reader's brain tired. There's a reason why fictions are written in plain serif fonts while book covers are written in fancy fonts. Too much styling in the text makes your brain use up extra processing power.
You do not want to give your readers headache from the font. Using too much font styling is the free demerits that you could've easily avoided by actually not doing it. Use your prose to provide a dreamlike, weird experience of a dream. Don't take the easy way out of italisizing the entire chapter.