Animate a clip or title (In, Loop, Out)

Every clip, overlay picture and title has three places for an animation:

Place	When it plays	Examples
In	As the clip starts	Fade in, Pop in, Slide in, Rise up, Bounce in
Loop	Repeats in between	Pulse, Float, Wiggle, Sway, Breathe, Heartbeat
Out	As the clip ends	Fade out, Pop out, Slide out left, Spin out

Add one

Select the clip or title. With nothing selected, it goes on the clip at the playhead.
Open Effects in the left rail and go to Motion. The line under it shows the clip's In, Loop and Out: press one to see its tiles.
Press a tile. The preview plays that part of the clip once, then stops where the clip is fully shown.

The inspector (Ctrl+Alt+I, both modes) has the same three rows: the Video tab for clips and pictures, the Animation tab for titles.

Do this	Where
Pick another animation	Press another tile, or the row's picker in the inspector
Make it shorter or longer	The row's length in seconds, in the inspector
Make it gentler	Strength, in the inspector
Remove it	The × next to it on the Motion line, or None in the inspector's picker

Select the clip and open the inspector's Video tab › More › Keyframes, enter and exit.
Point at a tile to preview it ("Pick one. Point at it to preview."). None comes first.
Click a tile, for example Zoom in, Pan right or Shake.
Under the tiles: Intensity, Length (s) and Whole clip. A change applies at once.

6 more details

Each pick or change is one Undo step (Ctrl+Z).
If a clip is shorter than In and Out together, both play faster.
Animations work on video, photo and title clips. A clip needs at least 2 frames.
They play on top of any keyframes you set yourself.
Captions have their own Word animation in their caption style.
The preview after a pick needs the player; a second pick, pause or a move of the playhead ends it early. Nothing is saved by the preview itself.