To create outlined text, adjust the Contour option in the text properties editor. Select a text frame, then click on the Text Attributes icon.
Under the Contour options, first choose a color to contrast with the text body color. Click on the color chip to choose a color on the color palette.
To increase or decrease the size of the outline, use the contour slider, or click the number next to the slide to type in a precise value.
To reduce the opacity of the text contour, click on the color chip then, on the color editor, reduce the opacity levels.