VBA speed up

Hi All,
I need to speed the below code up any ideas?

 Dim myWorksheet As Worksheet
    Dim myWorksheetName As String
    Dim count As Long
    Dim temp As String
    Dim count2 As Long

    
    If ComboBox1.value = "" Or ComboBox2.value = "" Then
    MsgBox ("Please select Month or Branch")
    Exit Sub
    End If
    
       temp = ComboBox2.value
       If temp = "All" Then
       temp = "*"
       End If
    myWorksheetName = ComboBox1.value
    
'check if exsists
 'call SheetExists

If SheetExists(ComboBox1.value) = True Then
        
    count = Sheets(myWorksheetName).Range("A1").CurrentRegion.Rows.count
    
    Worksheets(myWorksheetName).Range("A1:P" & count).AutoFilter _
    field:=4, Criteria1:=temp
    
  
     
     Worksheets("Sheet1").Range("A1:P2").Copy _
    Destination:=Worksheets("Sheet3").Range("A1")
    
     Worksheets(myWorksheetName).Range("A3:M" & count).Copy _
    Destination:=Worksheets("Sheet3").Range("A3")
    
    count2 = Sheets("Sheet3").Range("A1").CurrentRegion.Rows.count
    count23 = count2 + 1
     Sheets("Sheet3").Range("K" & count23).value = "Total"
     Sheets("Sheet3").Range("L" & count23).value = "=SUM(L3:L" & count2 & ")"
    Sheets("Sheet3").Range("M" & count23).value = "=SUM(M3:M" & count2 & ")"
    
    With Sheets("Sheet3").PageSetup
.PrintTitleRows = ""
.PrintTitleColumns = ""
.PrintArea = ""
.LeftHeader = ""
.CenterHeader = ""
.RightHeader = ""
.LeftFooter = ""
.CenterFooter = ""
.RightFooter = ""
.LeftMargin = Application.InchesToPoints(0)
.RightMargin = Application.InchesToPoints(0)
.TopMargin = Application.InchesToPoints(0.92)
.BottomMargin = Application.InchesToPoints(0)
.HeaderMargin = Application.InchesToPoints(0)
.FooterMargin = Application.InchesToPoints(0)
.PrintHeadings = False
.PrintGridlines = False
.PrintComments = xlPrintNoComments
.CenterHorizontally = False
.CenterVertically = False
.Orientation = xlLandscape
.Draft = False
.PaperSize = xlPaperLetter
.FirstPageNumber = xlAutomatic
.Order = xlDownThenOver
.BlackAndWhite = True
.Zoom = False
.FitToPagesWide = 1
.FitToPagesTall = 1
End With
     
 
     Me.Hide
  Application.WindowState = xlMaximized
   Sheets("Sheet3").Range("A1:M" & count23).PrintPreview
   Application.WindowState = xlMinimized
   Me.Show
     Worksheets(myWorksheetName).AutoFilterMode = False
    Sheets("Sheet3").Range("A1:P" & count23).value = ""
    Sheets("Sheet3").Range("A1:P2").UnMerge
     ThisWorkbook.Save
    Else
     MsgBox ("No Data For That Month Please Change")
     Exit Sub
     End If