It would help if you at least mentioned the make and model of scope. You should first read the scope's manual to see whether it has a function for displaying user messages. If it does, then look to see if the driver for the scope has that function in it. If it does, use it. If it doesn't, you can write the the function youself with a VISA Write. If the scope doesn't have a built in function to do this (and many don't), you're going to have to think of some other way.
