It is extremely easy to schedule article post for your future postings. While you write/edit your article in your wordpress blog, make sure that you edit/set the TimeStamp to the date in future which you want to schedule your article. Do not forget to PUBLISH your article (not SAVE). That’s all and your articles are scheduled for future postings. For instance if you want your article to be posted on Christmass, then set the TimeStamp to 25 December 2006 (for this year) and set your minute and second to your desired time.
Note - Keep in mind that the Edit TimeStamp should be checked/selected while editing an article. Just changing the date/time do not affect the TimeStamp unless you select that option.