I had to go through 21 plugin with a map and chisel on one of my employer’s projects recently. Most of them shared similar scripts, many added unused CSS. After inspection I realised, that all this mess could be shortened. But doing this manually would consume an exorbitant amount of time. Instead, I searched WP plugin database for an automated solution. And I have found it. It is called WP Minify. It does the tedious job of sorting your JS and CSS files, combining them, and compressing all together. In just one sitting you can improve your page loading time three times.
To make plugin working you shall need to allow server to write to plugin cache folder and to change its configuration files. This can be done with chown and chgrp commands. If you do not have access to them, ask your hosting provider to change permissions for these files respectively.