Text analysis allows you a keen comprehension of a text. it consists in two phases: Denotation, that  considers the surface of the text and the way the different parts of the text are linked together and connotation, that  goes deep into the text and helps you to find out possible hidden messages. It considers word choice, figures of speech, sounds and rhythm.  

Text analysis starts from the title: indeed  it's useful to make conjectures about the possible content of the text. Then, you must read the text to find out what it is about. After that, you must consider the layout (the way the text appears on the page that suggests you the genre of the text: poem, play...) and the structure(lines, stanzas). You can also revise the text to make it more fluent and easier to understand. Finally, you can go on with the connotative analysis, so try to find out the meaning of  the stylistic choices of the writer.

Remember that whatever text mutual depends on another one (intertextuality): the difference just consists in word choice and word order.