You are asking "how" to summarize Lorna Croizer's poem, "Without Hands."    For this poem, I suggest you simply summarize what it is in each stanza that couldn't be done without hands.

First, in case you are unaware, the poem was written to honor a Chilean musician, Victor Jara, whose hands were smashed by soldiers to keep him from playing his guitar to fellow prisoners while they were being kept in Santiago stadium.  After being tortured, he and thousands of others were killed, Jara in September, 1973.

For your summary, I will list the broad categories written about in each stanza, and leave the filling in of the details for you:

1. Machines, eating utensils, babies, music, and plums
2. Writers
3. Family or domestic life
4. The speaker's grandmother

The final three stanzas are unified by the subjects I've listed.  In other words, everything mentioned is an element of the subject I've listed.

The first stanza, though, touches on all five subjects listed. 

To summarize, simply write in your own words the subjects I've listed, in sentence form, of course, and fill in the most important details from each stanza.  For instance, a brief listing of the things a writer could not write about without hands for the second stanza would constitute a summary of that stanza.