“Invalid use of property” error when assigning a value in Word VBA

I have a Word document with two bookmarks. Upon saving the document I want to insert a certain text between those bookmarks.

Here’s what I tried:

Sub FileSave()
    Dim myRange As Range
    Set myRange.Start = ActiveDocument.Bookmarks("SaveDateStart").Range.End
    Set myRange.End = ActiveDocument.Bookmarks("SaveDateEnd").Range.Start

    myRange.SetRange Start:=myRange.Start, End:=myRange.End
    ActiveDocument.Range(myRange).Text = "Lorem Ipsum"

    ActiveDocument.Save
End Sub

But this gives me an error “invalid use of property” in the assigment of myRange.Start, as shown in the screenshot below.

What am I doing wrong?