In order to paraphrase a text, one needs to simply restate what the author is saying using words other then those used by the author of the text. Therefore, in order to paraphrase the poem The Tyger (by William Blake), one simply takes the poem, line by line, and provides different words (one is simply rewriting the poem in order to make is match their own dialect).
Therefore, an example of a paraphrase of the poem would look something like this (I am going to paraphrase the first two stanzas to provide you with an example of what it could look like):
(The poem's original line will be in italics and the paraphrased line will be bolded.)
Tyger! Tyger! burning bright
Tiger! Tiger! shiny and on fire
In the forests of the night,
In the woods at night,
What immortal hand or eye
What divine hand or eye
Could frame thy fearful symmetry?
Made you what you are?
In what distant deeps or skies
On what place on earth
Burnt the fire of thine eyes?
Made your eyes come to life?
On what wings dare he aspire?
What aspirations allowed him to he could do this?
What the hand dare sieze the fire?
What gave him the guts?
I hope this helps you to continue the paraphrasing of the poem. Keep in mind you are simply translating what you understand the lines of the poem to mean.