In a technical discussion forum about databases, someone posted an off-topic message: "to all Oracle staff, this phrase is not English: 'follow the below steps' How does this slip into Oracle Support tech note documents". Indeed, the English word "below" should not be used as if it was an adjective (see e.g. Wiktionary). But I've seen this incorrect usage for 20+ years especially in the IT industry. In the beginning, it mostly occurred in messages written by people with Indian-like names. Nowadays, Chinese or other ethnicities as well.
In any case, instead of saying "the below steps", we should say "the following steps", or "the steps below" (implying "located" before "below"). I'm guessing the adjectival usage of "below" is probably due to influence from the antonym "above", which *can* be used as an adjective as in "the above steps".
In light of the descriptivism vs. prescriptivism debate in which the latter has slowly lost ground in the past century, some people may argue that as more and more people start to use "below" as an adjective, this usage may eventually become accepted; after all, language evolves with the way it's spoken by the people. In fact, Merriam-Webster has already acknowledged this usage, after adverb, preposition, and noun. But for now, the majority of the native speakers and no other English dictionary consider this usage acceptable. It's wise to be standard-compliant and stop saying "the below steps".
(A good discussion is found on Daily Writing Tips.)