Run macro on row most recently added - vba

Question

I'm using a macro to generate an Outlook template based on data that has been entered into a workbook.
In the workbook I have 100 rows of data and 7 sheets.
I need to run the macro (on click of a button) on the most recent row's data and generate the template.
My rows contain time data (example 13:37, next row 14:02 etc) so I think that could be a good way to identify the latest row.
I'm using this code. I'm selecting the row using A203:G203
Sub NonConformanceGenerator()
ActiveSheet.Range("A203:G203").Select
Const HEADER_ROW As Long = 202 '<< the row with column headers
Const NUM_COLS As Long = 7 '<< how many columns of data
Const olMailItem = 0
Const olFolderInbox = 6
Dim ol As Object, fldr, ns, msg
Dim html As String, c As Range, colReq As Long, hdr As Range
Dim rw As Range
On Error Resume Next
Set ol = GetObject(, "outlook.application")
On Error GoTo 0
If ol Is Nothing Then
On Error Resume Next
Set ol = CreateObject("outlook.application")
Set ns = ol.GetNamespace("MAPI")
Set fldr = ns.GetDefaultFolder(olFolderInbox)
fldr.display
On Error GoTo 0
End If
If ol Is Nothing Then
MsgBox "Couldn't start Outlook to compose mail!", vbExclamation
Exit Sub
End If
Set msg = ol.CreateItem(olMailItem)
Set rw = Selection.Cells(1).EntireRow
msg.Subject = ""
html = "<style type='text/css'>"
html = html & "body, p {font:11pt calibri;padding:40px;}"
html = html & "table {border-collapse:collapse}"
html = html & "td {border:1px solid #000;padding:8px;}"
html = html & "</style>"
html = html & "<p>Hello,</p>"
html = html & "<table>"
For Each c In rw.Cells(1).Resize(1, NUM_COLS).Cells
If c.Column <> 0 Then '<<< This removes the 4th column if you type number 4 after the <> symbols
Set hdr = rw.Parent.Cells(HEADER_ROW, c.Column) '<< get the header text for this cell
html = html & "<tr><td style='background-color:#FFF;width:200px;'>" & _
hdr.Value & _
"</td><td style='width:400px;'>" & Trim(c.Value) & "</td></tr>"
End If 'we want this cell
Next c
html = html & "</table>"
msg.HTMLBody = html
msg.display
ActiveSheet.Range("A15").Select
End Sub

Answer 1

Is the newest row always at the bottom of the spreadsheet? If so, you can use Cells(Rows.Count, "A").End(xlUp).Row to return the last row with data in Column "A" for instance.
You could do something like this for use in your example.
With ActiveSheet
.Range("A" & .Cells(.Rows.Count, "A").End(xlUp).Row).Resize(1, 7).Select
End With