Add the Transition
When you've arrived at the settings you want, drag the transition to the Timeline (either the Clip Viewer or Timeline Viewer).

Transition in Clip Viewer
Transition rendering in Timeline Viewer[View full size image]
Making a Movie in imovie HD and iDVD 5: Visual QuickProject GuideBy
Jeff Carlson...............................................Publisher: Peachpit PressPub Date: April 01, 2005Print ISBN: 0-321-33018-8Pages: 144Index

Transition in Clip Viewer
Transition rendering in Timeline Viewer[View full size image]