First, you need to upload your .swf file on any host in the internet. This step makes sure that your .swf file is always available to access. For me, I used my unix host of RMIT unix sever to store my file.
Then, apply the followings codes into your blog:
<OBJECT classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,0,0" WIDTH="320" HEIGHT="240" id="Yourfilename" ALIGN="">
<PARAM NAME=movie VALUE="Yourfilename.swf"> <PARAM NAME=quality VALUE=high> <PARAM NAME=bgcolor VALUE=#333399> <EMBED src="Yourfilename.swf" quality=high bgcolor=#333399 WIDTH="320" HEIGHT="240" NAME="Yourfilename" ALIGN="" TYPE="application/x-shockwave-flash" PLUGINSPAGE="http://www.macromedia.com/go/getflashplayer"></EMBED></OBJECT>
Finally, replace "Yourfilename" by the real link of your .swf file (after upload your file on a host, you will receive a link to download your file). Your Flash movie will be already displayed on your blog. ^^
You also can change the width and the height of display window. Have fun!
If you want to learn more about this, please visit this site http://animation.about.com/od/flashanimationtutorials/qt/embedswfwebpage.htm