How to upgrade/install flash player for firefox in Linux (CentOS)

In CentOS Linux, if you're browsing a site and firefox requires you to upgrade the flash player, here's a general procedure how it's done.

1. Click the download or flash player button to redirect you to adobe's flash player download page.
2. Download the corresponding version, e.g 32 bit or 64 bit (usually saved by default on /tmp folder.
3. Close firefox for now.
4. From a console, go to the directory where you downloaded the flash player, named libflashplayer.so (/tmp in this sample).
5. From /tmp folder type cp libflashplayer.so /home/jun/.mozilla/plugins (where jun is your linux username)
6. Open firefox and your flash player should be working ok by now.