Please excuse my messy handwriting but I was practicing with my tablet ^^
Open the Rar file
Search the file names for a number, that will tell you what folder to put the files in.
Go to you Feralheart>> my_presets folder and put it in the folder with the same number.
Replace the old .material file with the new downloaded one.
Open up Feralheart and go to Preset Maker then find the one with the same name as the folder. Then press Export if the preset is working.
Log into the game and on the last tab click that "Use Preset" button and find your preset.
That's all there is to it