The rules for rewriting the Text are simple:

Try to fit your poem into
the same space as Blake used

If you are sending in your own
poem about a Tyger:

Write no more than 141 words
using up to 24 line breaks

If you are sending in a copy of Blake’s Text:

It must be in the .jpg file format

It must be 376w x 407h pixels
or a standard A4 sheet of paper