Right click sheet tab>view code>copy paste this
Now whatever selection you make will be colored with number 6
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Cells.FormatConditions.Delete
With Target
.FormatConditions.Add Type:=xlExpression, Formula1:="TRUE"
.FormatConditions(1).Interior.ColorIndex = 6 '35
End With
End Sub