Add extra details to your diagrams with callouts to make those details stand out.

Add a callout to a shape

  1. Select a shape.

  2. Select Insert > Callout.

  3. Select a callout style to see a preview.

  4. Select the callout style you want.

  5. With the callout shape selected, type in the callout text.

  6. Drag the callout shape to reposition it.

  7. Select a blank area of the drawing page to finish.

    Note: When a callout is associated with a shape, the callout moves with the shape automatically. If the shape is copied or deleted, the callout is copied or deleted too.

Move the callout to another shape

  1. Select the callout.

  2. Select the control handle, and drag it to the shape you want to associate the callout with.

  3. Drag the callout shape to reposition it.

Source: Microsoft