1. Go to https://icomoon.io/app/#/projects
2. Click on "Hamburger" > "Import Projects"
3. Select "hustle.json" config file
4. Do whatever you need to do
5. Download updated font icon, replace it in theme and update "_icons.scss" file.. just the necessary part after "//generated by iconmoon"
6. Download updated config file from https://icomoon.io/app/#/projects and replace orginal one in GIT.