Motion 5 - How do I make my timeline longer?

Select the Project (the very topmost item) in the Layers list.

In the Inspector, select the Project tab and enter a new duration.

Afterwards, you can drag the In and Out boundaries in the timeline:

What I showed you was a "Motion Project", and you are working on a "Motion Title".

For some reason (don't ask me why, I don't know...), the way to change the duration is slightly different.

To change the duration for a title, you have to go to Properties instead of Project.

Luis had the right information, he just showed you the wrong inspector tab. When you select the Project "layer", in the Inspector, you need to select the **Properties** tab, not the Project tab. You will then have access to the timing.

There is another shortcut:

This is the timeline timecode control. Notice the analog looking clock on the left side - it is showing the time of (approximately) 12:08.

If you click on the clock the time changes to 12:15

and the time showing is the Project Length. You can click and drag on the clock to change the project timing.

You can also double click on the time and type in the length. All timecode in FCPX and Motion handle a typing shortcut. For instance, if you need to make the project 5 seconds long, you can type "5." (then Return) and Motion will provide the "00" frames. You can also type in something like 1.4.3 and Motion will make the project 1 minute, 4 seconds and 3 frames long. Generally, you can skip placing '0' values altogether (unless you mean 20 frames instead of 2 frames).

Click on the clock icon again to return to the timeline timecode.