Hi,
Here is sample code for a change event:
Private Sub Worksheet_Change(ByVal Target As Range)
Dim isect As Range
Set isect = Application.Intersect(Target, Range("A1"))
If Not isect Is Nothing Then
'Your code here
End If
End Sub
If this is for sheet1 then
1. press Alt+F11
2. double click the Sheet1 object in the top left corner of the screen (the
Project window)
3. add your code.
In your case you may want to record the sort routine so you can put it into
the "your code here" location.