https://growingorganic.com/soil-guide/coots-soil-mix/
Follow the Coots mix..u can add on whatever else you have too.
Humic acid is about 1/2 cup every 3-4 cubic feet. 1 tables spoon of Epsom salt per cubic foot.
Most important part for you is buying or making an inoculater like homemade EM1 or...