Here’s the step by step procedure, to enable / activate remote publishing in WordPress :

1> Login to your WordPress blog as administrator.
2> You’ll see a bunch of links in the left sidebar, click on ‘Setting’ –> ‘Writing’
3> Once you are in the ‘Writing Settings’ page, scroll all the way down and you’ll find ‘Remote Publishing’. Enable both ‘Atom Publishing Protocol’ and ‘XML-RPC’ and click on ‘Save Changes’

Your self hosted wordpress blog’s now setup for remote publishing. You can use third party software like Windows Live Writer / Word 2007 to publish articles in your self hosted wordpress blog.