You can move a clip in time by clicking on it and moving it to the left or right in the timeline. If you select a clip you can press [ to move it 0.1 s to the left and ] to move it 0.1 s to the right. Shift-[ moves the clip 1 s to the left and shift-] 1 s to the right.
Below is an example of moving the logo.png
clip so
that it now starts at time 1s (one second) in the presentation.
Here is the original state of the presentation, with
logo.png
starting at time 0:
If you now press shift-] the result is moving
logo.png
to start at time 1s (one second):
When you play this presentation the logo will not appear until 1 second into the presentation.
