Introduce quotes, and explain them if necessary.
When you quote, you need to introduce the quotation. Tell the reader whose words they’re about to hear, and where those words came from.
And unless the meaning of a quotation is self-evident (i.e. really obvious) it’s a good idea to follow the quotation by explaining what you understand it to mean.
In They Say, I Say, Graff and Birkenstein call this a “quotation sandwich.” (See TSIS Chapter 3, “The Art of Quoting.”)
start quoting “out of the blue,” without telling the reader whose words they’re about to hear.
assume that your reader understands what a quote means