>>41473542r u new?
many phones save the rotation information into the EXIF data, when posted to 4chan, the EXIF is stripped for privacy reasons.
To prevent this from happening, open up the photo in a photo editor (paint if you're on a windows PC) and make sure it's rotated the way you want then "save as", this will hardcode the rotation information so when the EXIF is stripped, it retains the orientation you want.