Ms word, trying to rid of red markings in mark up view, permanently?

I have been given a word doc to edit. But it has red markings in it to show past deletes and things like that. I want to get rid of those red markings permanently. How do I do that. When I go to the header and click, the red markings come back. I originally did get rid of them by going to view/markup and clicking markup which was clicked. But then when I doubleclick the header to edit a inserted picture, the red reappears. thanks