Private Sub Workbook_Open()
    Dim lastRow As Long     'last row with data
    Dim thisDate As Double  'start timestamp
    thisDate = Now()
With Sheets("Pressure Log")
    lastRow = .Range("B" & .Rows.Count).End(xlUp).Row 'populate next row with date/time
    .Range("B" & lastRow + 1 & ":G" & lastRow + 1).Borders.LineStyle = xlContinuous
    .Range("B" & lastRow).Offset(1) = Format(thisDate, "dddd")
    .Range("B" & lastRow).Offset(1, 1) = Format(thisDate, "mm/dd/yyyy")
    .Range("B" & lastRow).Offset(1, 2) = Format(thisDate, "hh:mm AM/PM")
    .Range("B" & lastRow).Offset(1, 3).Select 'position for data
End With
End Sub