IPhone folder icons

My old eyes are not as good as they once were and it sure would be helpful to have a picture icon instead of small font text to help identify folders on my iPhone. For example I use both written text messages as well as verbal text messages through the app called Hey Tell and I would like to put them in the same folder and would prefer to have the same icon that is presently used for written text messages (or something similar) to be the icon to open up the folder. Hopefully that makes sense. Any of you creative geniuses have a solution for those of us with less than 20/20 vision? As always I appreciate the help.