In the documentation folder of the download upgrade.txt and changelog.txt.
Basically in laymans terms unzip the download delete install.php config-inc.php config-int.php header.htm footer.htm and then upload everything else to your site overwriting your photopost and run upgrade.php and select to upgrade 5.62 to 6.0 link. Thats it.
You can remove the uploads and data folders if you wish but uploading them will not harm anything either. I just posted easy instructions above for you.