Remove any snow covering the stairs with a shovel or a broom. Ice itself is slippery, but snow on top of ice is even slipperier. Removing any snow will increase your safety while removing the ice.
Start at the top of the stairs and use the English shovel to chop downward into the ice. The edges of the ice layer will be the weakest, so start there. Do not worry about damaging the steps. The cured concrete can stand up to your ice removal. Leaving the ice on the steps is more likely to cause cracks in your steps.
Shovel ice chunks off the side or further down the stairs after you've chopped the ice into chunks. Be certain to clear all the chunks off the steps before continuing. This will improve safety as you work.
Repeat the chopping and clearing process for each step as you move down the stairs. Moving down the stairs will keep completed steps from accumulating shards of ice.
Spread sand on the steps to increase traction once the steps are cleared of ice. Sand will not melt the ice, so there will be no damage to the concrete.