Eucalyptus leaves make rich, nutritious humus like any other leaves. But leaves should never be the sole material in your compost pile. The microorganisms in your compost pile need a balance of green material like living plant and kitchen waste and brown material like dried leaves, paper or hay to break down matter effectively. If you don't have any straw readily on hand, consider buying a bale to add to your compost pile each time you deposit a pile of eucalyptus leaves or other green material.
Use pruning shears, a shredder or your lawnmower to break the eucalyptus leaves into the smallest pieces possible.
Spread the leaves over the top of the pile.
Shred or break up twice the amount of leaves by volume of brown material and add that to the pile.
Moisten the top layer of the pile by lightly sprinkling it with the hose.
Turn the pile so that the ingredients are thoroughly mixed. Continue to turn the pile (at least once weekly or whenever a compost thermometer shows that there has been a drop in the pile's internal temperature) and add material as usual.