First, your contribution must be converted to one of the Yahoo approved file types listed at

http://help.yahoo.com/help/us/geo/gfiles/gfiles-24.html

 

If it is not then you need

 

To check how your contribution will appear on your pc:

Note that it may appear differently on other pcs due to different screen settings and/or different programs invoked by different settings of File Type in Windows Explorer.

 

If you do not like what you get, a few courses of action are available;

 

The policy of the web site is that the site should be as simple as possible so all files should be viewable with  standard Windows 98 and Microsoft Internet Explorer 5 or later. So Adobe files are avoided as far as possible.