Ensure that the source text is in a language you do not understand
Place the source text on a suitable piece of furniture (e.g. a desk, or a side-table) at one end of the room
Walk across the room to the other end. (Depending on the size of your room and the quality of your vision.) You should be far enough so that the letters are no longer distinct, but close enough to still see the shape of the words.
Without forcing any interpretations on yourself, take note of the first image that comes to mind when you see the text
Repeat the above for every page of the source text.