What are some poetic devices in the poem "Then and Now" by Oodgeroo Noonuccal (formerly Kath Walker)?

In the second grouping of lines, the didgeridoo, a large wooden instrument used by Australian aborigines, is personified as "Calling us to dance and play." Personification is the attribution of human qualities to something that is not human. An instrument cannot willfully call anyone to do anything, but the person playing the instrument might be using its sound in order to call someone to so something. Therefore, this line constitutes a personification of the didgeridoo.
In the final grouping of lines, the speaker uses refrain, the repetition of words or phrases, in order to draw more attention to and reinforce how much she has lost in the change from aboriginal culture to the dominant, white culture. She says,

No more woomera, no more boomerang,No more playabout, no more the old ways.

She repeats the words "no more" four times in these two lines rather than use a conjunction like "or" in order to allow her losses to seem to build, to snowball. In addition, the lack of a conjunction like "and" after the final comma and before the last item in this series, or list, is an example of asyndeton. Asyndeton is the exclusion of this conjunction, and it is used in order to achieve a similar, snowball, effect. Further down, the speaker says,

Now I am civilized and work in the white way,Now I have dress, now I have shoes [...].

There is some irony in the first of the two lines above. People normally talk about being "civilized" as though it is a good thing, but it seems to be a negative here. Irony is created when what happens is the opposite of what one expects; we expect "civilized" to be a good thing, but, for the speaker, it is clearly not. The speaker has lost so much in order to become "civilized" and now she must work in "the white way," existing in the manner dictated by the white, rather than aboriginal, world. She repeats the words "now I" three times in these two lines to draw attention to the lackluster qualities of what she's "gained" compared to all that she's lost. In the final two lines, the speaker says,

Better when I had only a dillybag.Better when I had nothing but happiness.

People tell her how lucky she is to "'have a good job,'" but she does not feel lucky. The repetition of the words "Better when" in the lines above reinforce how superior her youth, her happiness as a "child of nature," was compared to her "civilized" and empty adulthood. In the two lines above, the refrain of "Better when" can be more accurately described as anaphora, which is the repetition of words or phrases at the beginning of lines.

The author uses several poetic devices in the poem "Then and Now." The first stanza includes the use of onomatopoeia in the phrase "grinding tram and hissing train," which helps the reader add sound to the imagery of the modern industrialized city. There are also many instances of alliteration throughout the poem. "Teeming town," "traffic and trade," and "white ways" are a few good examples of alliteration.
The author uses repetition to help the reader focus on her theme in the poem. The speaker is lamenting the changes that have occurred over her lifetime. By repeating the words "now," "one time," and "no more," Noonuccal draws the reader's attention to the changes and evokes a feeling of nostalgia for the old Aboriginal ways.
The author also uses colloquial language in the poem to help develop the theme of how times have changed. By using Aboriginal words such as "corroboree," "didgeridoo," "woomera," and "playabout," the author is highlighting how different the culture of the speaker's childhood was from the life that is going on around her.