Follow steps below:

Hello Alan, Mister Micawber, Beeesneees, Mordant, Esl_Expert and other native English speakers,
Follow [color=red]steps below:

  1. Turn off the machine’s power switch. Unplug the telephone line cord first, disconnect all cables, and then unplug the power cord from the AC power outlet.

  2. Lift the document cover (1). Clean the white plastic surface (2) and scanner glass (3) underneath it with a soft lint-free cloth moistened with water.

Is [color=red]steps correct without “the”?

Not really, no.
It is an acceptable convention to omit words like this when writing in note form rather than in complete sentences. However, as the rest of the instructions are in full sentences, rather than in note form, then the article should have been included, so that the format of the entire text matched.

Thank you, B.