How to work for liberating ALL living beings?

I am given to understand that a true Buddhist seeks tirelessly to liberate from the suffering (dukkha) of existence all living beings, and not only humans. Attainment of Buddhahood depends on such actions on an ongoing basis, I am told. Based on this, my question is: 1) Apart from generally showing compassion and benevolence towards all living beings, in what ways do accomplished Buddhism practitioners work for the liberation of living being as diverse as, say, ants, pine trees, salmon and e-coli bacteria? What do the scriptures say, and what do the more recent writings say on this matter? 2) How do accomplished Buddhism practitioners liberate from dukkha the beings of non-earthly nature of other lokas, such as angry deities and hungry ghosts? What do the scriptures say, and what does recent literature say?