Tompen78's suggestion builds a list one paragraph at a time into a full list but does not answer the OPs request that at ANY time ONLY 1 bullet be seen during the animation

However, it does save time in the first step to do it this way. After the entrance and exit animations are set to the text box, move over to the animation pane.

• Set the animation pane so you can see all the sub-animations (each bullet).
• Rearrange the order of the sub-animations (this can be done by drag and drop once all the subanimations are visible
• Set the timing on each exit animation to be WITH PREVIOUS.