Help with IcoMoon to reduce the size of fontawesome files to be used on our site. Decrease CSS file sizes, increase Page Speed

We are currently using font icons such as fontawesome. However, we only use a few fonts, but when you implement the fontawesome css code it creates a large file size. We want to use a service such as Icomoon to help reduce all the css and related file sizes. Because we do not use all the icons within the fontawesome, we want to only load the ones that we actually use. This will increase page speed. Hopefully someone has experience in this and can help us implement our own