In 2 Kings 9 we read (ESV):
11 When Jehu came out to the servants of his master, they said to him, “Is all well? Why did this mad fellow come to you?” And he said to them, “You know the fellow and his talk.” 12 And they said, “That is not true; tell us now.” And he said, “Thus and so he spoke to me, saying, ‘Thus says the Lord, I anoint you king over Israel.’” 13 Then in haste every man of them took his garment and put it under him on the bare steps, and they blew the trumpet and proclaimed, “Jehu is king.”
Clearly the actions of the commanders were indicating their collective support of Jehu's anointing as king.
There are many ways one can indicate one's support of a person anointed as king. But why did the commanders think it appropriate to show their support by removing their clothes and putting them under Jehu? They did it in a hurry too, as though it were obvious that this is just 'what you do' in that situation. Is it just one of those cultural oddities whose meaning is now long forgotten?