Your 14 line sonnet must be written in three sets of four lines and one set of two lines.
1. The first quatrain will have lines that end in a rhyme scheme like this: ABAB, for example, ‘day’, ‘temperate’, ‘may’, ‘date’.
2. The second quatrain will use different words to rhyme scheme like this: CDCD, for example, ‘shines’, ‘dimmed’, ‘declines’, ‘untrimmed’.
3. The third quatrain needs different words again, to rhyme scheme like this: EFEF, for example, ‘fade’, ‘lowest’, ‘shade’, ‘growest’.
4. You now have your three Shakespearean quatrains – that’s 12 lines. Remember that a Shakespearean sonnet always has 14 lines, so you need two final lines – called a couplet. The rhyme scheme for this is GG, using words you haven’t used in the rhyming so far, for example, ‘see’ and thee’.
The rhyme pattern of your 14 line sonnet should now look like this: ABAB CDCD EFEF GG