log into your Cpanel and look for the R1soft icon, if you've got that in your cpanel, you doont need to backup your site files, its done foryou by the R1soft backup system, click on that and you can restore your site files from there.
you will need to backup your database though,
in Cpanel, click on the phpmyadmin icon, then on the next page, on the left hand menu, click on the database for your wordpress (not the one that says _schema) then on hte next page, on the top menu, click export and save the file to your computer as an .sql file.
If there are any problems with updating your wordpress or plugins, use the R1soft function to restore your site files to a previous state and then upload the .sql file you downoaded from phpmyadmin,
to upload the .sql file, same as you did when you exported it, only click import instead, find the file you need and cliclk go
