Indeed, just "make something" is way to broad, you need to give the artists basic concept you would want, like letters, colors, graphics etc.
Try to picture in your mind what you would like then transfer it into letters, as much details as you give the closer the design can be made to fit your imagination by the artists.
I presume it would be initials or a name you are looking for, however, you need to kick in some extra wishes to get the design going. Not just any name or initials can be written now can they ^^