Click the Preview Slider button on the
preview slider bar, located at the bottom left corner in the Title window, and drag to the right.

Note
The Title Window Slider previews only the text; not special timings. Special timings depend on the clip's duration in frames; so, you must add the title to the Timeline and preview the title with its special timings in the Timeline.
When you started the preview, you may have noticed that the text was already on the screen at the beginning of the roll; when the roll ended, the last word was still on the screen, at the bottom. To make the text roll onto the screen instead of starting on-screen, you need to insert blank lines before the first word of the text. Similarly, you add blank lines to the end of the text if you want the text to roll all the way off screen at the end.
For this lesson, the Octopus poem rolls onto the screen at the beginning and then stays on-screen at the end.