After that, you can right click the corresponding point or feature on the track to be aligned. Continue holding the right mouse down, and move it up and down, watching the correlation window. When that window peaks, you have a match.
You must immediately register your match by pressing the enter key. If you want to abort the match, immediately hit the delete key.
You can save your work at any time by saving the current session. Then, by restoring your session at a later time, you can resume.
For more detail, see Compositing: Step by Step