Start by thinking of comparative nouns.
e.g. castles, fortresses, guardians, soldiers.
Gather a bank of associated verbs.
e.g. guarding, looming, protecting, shielding
Use a metaphor for the rainforest trees.
e.g. The trees were a sleeping head of giants guarding their subjects.
Gather some sound words to describe the rainforest.
e.g. chirping, chattering, howling, yowling, shrieking, tweeting, chittering.
Think of some associated musical language.
e.g. radio, concert, tenor, descant, octave, orchestra, symphony, cacophony, performance.
Start with the provided sentence and then create your own sentence that starts with three onomatopoeic words. Remember to use musically associated language.
e.g. As the film zoomed in, Jelly could see the parrots, glorious parrots. Squawking, screeching, hooting, the choir of the canopy awoke.
Think about this simple sentence; The parrots sang together in harmony.
Now, create some relative clauses.
e.g. which were drenched in sunbeams, which were majestic and exotic.
Use one of your relative clauses to improve the sentence.
e.g. The parrots, which were illuminated by the sunlight, sang together in harmony.