When downloading a census page or viewing census on microfilm, look at the page numbers that are written on the page. There might be more than one. View the previous image on the website or the microfilm roll. View the one before that.
How many different page numbers are written on the census page/image?
An 1810 census entry from Bourbon County, Kentucky indicated three sets of page numbers. One was stamped, one was written in ink (apparently) and another looked like it was written in pencil. And sometimes the page numbers are one every other "page."