Can I optimize and speed up my VBA code - vba

Question

I am no VBA guru, but capable enough to stitch together the below code. It essentially formats a Invoice to hide any empty rows (populated with vlookups, but no value returns ""), set to 1 page portrait and export to PDF.
My issue is:
The code is taking way to long to run from start to finish.
Below is the VBA code I want to optimize and speed up.
Sub Save_Quote_As_PDF()
Application.ScreenUpdating = False
Dim a As Long
For a = 1 To ActiveSheet.Shapes.Count
On Error Resume Next
With ActiveSheet.Shapes.Item(a)
.Placement = xlMoveAndSize
.PrintObject = True
End With
Next a
On Error GoTo 0
ActiveSheet.Range("DCANUMBER").SpecialCells(4).EntireRow.Hidden = True
Dim PdfFilename As Variant
PdfFilename = Application.GetSaveAsFilename( _
InitialFileName:=ActiveWorkbook.Path & "\" & ActiveSheet.Range("N2").Value, _
FileFilter:="PDF, *.pdf", _
Title:="Save As PDF")
If PdfFilename <> False Then
With ActiveSheet.PageSetup
.Orientation = xlPortrait
.PrintArea = "$A$1:$K$78"
.PrintTitleRows = ActiveSheet.Rows(19).Address
.Zoom = False
.FitToPagesTall = 1
.FitToPagesWide = 1
End With
ActiveSheet.ExportAsFixedFormat _
Type:=xlTypePDF, _
Filename:=PdfFilename, _
Quality:=xlQualityStandard, _
IncludeDocProperties:=False, _
IgnorePrintAreas:=False, _
OpenAfterPublish:=True
End If
ActiveSheet.Range("DCANUMBER").SpecialCells(4).EntireRow.Hidden = False
Application.ScreenUpdating = True
End Sub

Answer 1

To hide the blank rows:
Dim ws As Worksheet
Set ws = ActiveSheet ' ActiveSheet is of type Object so using type Worksheet is a tiny bit faster
Dim row As Range ' again, specifying the type makes it a tiny bit faster
For Each row In ws.UsedRange.Rows ' .UsedRange to limit the range to only the used range
If row.Find("*") Is Nothing Then
row.EntireRow.Hidden = True
End If
Next
I don't think that hiding the rows is the slowest part of your code. You should time your code to see what parts are the slowest:
Dim start As Single
start = Timer
' part of the code
Debug.Print CDbl(Timer - start), "part 1" ' CDbl to avoid scientific notation
start = Timer ' remember to reset the start time
' another part of the code
Debug.Print CDbl(Timer - start), "part 2"