Depending on your requirements the easiest way to do this is to upload your swf (Flash) file into a blog (using the blog tool bar) then copy the location (where the file has uploaded to) into a "Text box" in you main page (add another if required). Be sure to use the correct html embed code: embed src=“http://........swf” pluginspage="http://www.macromedia.com/go/getflashplayer" type="application/x-shockwave-flash" name="obj1" width="250" height="250" quality="High" bgcolor="#FFFFFF".....
Alternatively upload your file to another server and use that URL.