Using nested block and loop structures is often a necessary part of any VBA macro. Multiple nested structures can be very long and difficult to follow when trying to read and debug the code. To aid in the legibility of your code always indent the code within the block or loop structure. For longer running structures copy the initial test expression and paste it as a comment after the closing statement. See the example macro below.
‘Example showing use of indents and comments
Public Sub MyMacro()
Dim FileIsOpen As Boolean
Dim iCount As Integer
'Do stuff here
'Indent lines of code under every block and loop
'Add comment after block/loop closing statement
If FileIsOpen Then
For iCount = 0 To 10
Select Case iCount
Case 0
'Indent 0 condition code here
Case 10
'Indent 10 condition code here
Case Else
'Indent Else condition code here
End Select 'iCount
Next 'iCount = 0 To 10
Else
MsgBox "File is closed", vbInformation, "MyMacro"
End If 'FileIsOpen
'Do more stuff here
End Sub