See this thread for more on how to do this: 2D Text around a circle?
[added] I generally explode the text and then group each letter and then use @Geo’s approach to place the letters around the circle. I pick a size and then as I start putting them in place, I quickly see that they need to be larger or smaller to space things in order to come out evenly. In the case of your life rings, you can import an image (even if it’s fuzzy) to help get the size of the letters without too much trouble.