How can I position an object on the center line of the page?

I am creating a piano duet and am trying to set up a pdf where the first page is player one's first page, then player two's, then player one's second page, followed by player two's, and so on. I've got that part down, it's just that I need to have text at the top that clarifies whose pages are whose. I have tried using a text box, but for some reason musescore just won't let me move it. Any other method I can do but I need to get it right in the center. Help please!