"Sonnet 75" by Edmund Spenser is written a Spenserian sonnet, a form which he devised himself. This form of sonnet divides the poem into three quatrains (stanzas of four lines each), followed by a couplet.
In a spenserian sonnet, the first three quatrains often share similar or loosely related ideas, and the couplet at the end often suggests a new idea or commentary on the above stanzas. The rhyme scheme of a spenserian sonnet is ABAB/BCBC/CDCD/EE.
Spenser's "Sonnet 75" meets all these criteria, telling of the speaker's wish to write his love's name on the sand in the first stanza. In the following stanzas, the woman says that he should not try to "immortalize" her, and Spenser concludes in the final couplet that even after death, their love shall live on.