Theory:

Alliteration is the occurrence of the same letter at the starting of two or more words in a single line, in a poem.
Example:
1. The slender smiling girl...
2. The song of sweet birds...
3. Black bug bit a bear...
4. Practise the piano...
What are the uses of alliteration?
  1. It creates a rhythm, similar to rhyming words.
  2. It emphasizes the importance of phrases.
  3. Mostly used in tongue-twisters.
Alliteration used in the poem "Indian Seasons":
Summer comes
in a blaze of heat
with sunny smiles
and dusty feet

Then seasons change
to muddy roads
monsoons and mangoes
leapfrogs and toads

Spring is pretty
but short and sweet
when you can smell the grass
from your garden seat

Autumn is English
in red, yellow and brown
Autumn is Indian
whenever leaves fall down

                                   ~ Nisha Dyrene
Reference:
State Council of Educational Research and Training (2019). Term-3 English Standard-6. Indian Seasons - Nisha Dyrene (pp 81-83). Published by the Tamil Nadu Textbook and Educational Services Corporation.