How do I enable uploading

From PaulGuWiki

File uploads are an often-used feature of MediaWiki, but are disabled by default in all current release versions.

To enable them, first make the upload directory (default images) writable by the web server (chmod 777 or allow the Apache user to write to it, etc.), then set $wgEnableUploads to true in LocalSettings.php (i.e. "$wgEnableUploads = true;").