I needed to add an effect to a text cation. I selected the caption and, on the Timing Inspector, Effects area, I chose Entrance from the third drop-down menu. From the bottom of the Entrance Effects, I clicked the move right icon (>) and chose Fly in From Right.
On the Timing Inspector, the Effect was been added to the Applied Effects List. If I needed to delete the Effect, I could easily do so by clicking the Trash icon to the right of the Applied Effects List drop-down menu.
On the slide, I noticed that an FX had been added in the upper right of the selected Text Caption. In addition, there was a red line starting on the Pasteboard and ending up on the caption.
I went on to add a second effect to the object. Upon previewing the effect (via Preview > Play Slide), I noticed that both effects occurred at the same time (I wanted one to occur and then, after a brief delay, the other). That was easy to fix via the Timeline.
... then I dragged one of the effects right on the Timeline, and then changed its timing.