Use the "event wizard" and then the "display wizard" to get an easier way to format your display message. You can use a place holder like "%s" to indicate where you'd like your variable to be placed in your string. Then, use the rest of the data parameters (ie: "Data2") to put in the names of your variables.
Format String (Data1): "my string is: %s"
Variable (Data2): myVariableName
This would print something like "my string is: hello world" if your variable "myVariableName" was a string type.
The placeholder "%s" works for most everything, but you can also use other formats like "%d" to add more detail. For example, if you wanted to have leading zeros to three places for an integer variable, you could use "%03d". Or, if you needed a printing in ascii hex, you could use "%x".