In the General Administration tab, clicking this icon: you are on the page of the Install function.
This feature will allow you to automatically install the zip update, a plugin, a skin, you just have to select the correct zip and a few clicks.
Warning: Guppy gives you the maximum file size to download, in this example 12Mb.
If your site is hosted by Free, you will have as maximum size 2Mb, it means that you can not use the install function for files <= 2Mb
If the archive is more than 2Mb, you need to install, unpack and put online by ftp.
A click Browse, select the zip file to install, then click Load File to download.
If the designer of the archive was made with MKZip, you have all the information as above before clicking Install this ZIP file.
Finally click on the ZIP file to install and that's it.
Never install a patch, a plugin, a skin has never been so easy, you will not have any excuse for not patching to move to the latest version.
A patch always brings a plus novelties, sometimes urgent corrections to the security of your site.