Answer:
For this question I have provided two methods.
METHOD 1:
Read the first line of the poem twice, and try as hard as you can to remember it.
Then, close your eyes and try an recite that line. Say it five times without looking, or until you can remember that line flawlessly.
Next, read the second line twice, and try to remember it. Close your eyes and recite the first line, then the second. Repeat five times or until you can remember it flawlessly.
Repeat with the other lines, gradually, you will begin to learn the poem, line by line.
This Method is slow but effective.
METHOD 2:
Get a blank book. Copy the poem onto a blank page.
Copy the poem again on another blank page.
Keep copying it until you think you remember it. Then try and write the poem on a blank page without looking at or copying from a previous page. If you are COMPLETELY stuck, look back at the page to remember it.
I hope I have helped whoever reads this. If you do not understand it, or there are grammar problems, please let me know so I can change it.