Begin by going to Administer > Content management > Content types (admin/content/types) and clicking the "Add content type" link at the top of the page.
ArticlearticlePromoted to front page option.The custom fields will include article_teaser_text to serve as a custom-written teaser which will be displayed only in the context of teaser views of the content but not on the full article, and article_subtitle, which is a sub-title about the article that will only be shown on the full version of the page but not in the teaser. You can of course add as many additional fields as you need.
article_teaser_text, and for Label enter: Article Teaser.Text and press "Continue".Text field, and press "Continue".Text area (multiple rows). Keep in mind that with most WYSIWYG editors, setting a text field to be "multiple rows" usually activates the editor on that text area, which is probably excessive in this case (though your WYSIWYG settings page may allow you to selectively disable these). Generally for a small text field of this sort I don't recommend HTML, and especially not WYSIWYG. If you change your mind you can always adjust this setting later.Required option, and enter a number for Maximum length such as 100 (it's usually ideal to set a maximum number of characters for the teaser to ensure it fits within the area you allot to teasers in your theme, and to enforce keeping teasers short and to the point for your readers). It's worth noting that Maximum length can only apply to a Text field kind of field -- the HTML textarea tag that the Text area (multiple rows) option creates is not capable of having a maximum length set (which is a limitation of HTML itself, not Drupal - you can however impose a maximum length on this tag using JavaScript).Filtered HTML (again not recommended, as the HTML counts towards the character limit, not to mention the purpose here is just a short bit of teaser text so ideally it should be kept simple... save the fancy stuff for the full article).article_subtitle, and for Label enter Article Subtitle.Text and press "Continue".Text field, and press "Continue".Required option, but you can choose to make this optional if you prefer.Hidden, Teaser to Hidden, and leave Full Node set to Default.Hidden (the reason for this is because this field will "only" ever be used within the context of Views module, which will call it up in its own way, so we want to hide it in every other case).