Wash grains 5 times or more while rubbing with your fingers to remove the coating that is bad for tummy and prevents proper absorption of nutrients.

You may also let it soak in water.

Heat pan and coat with your favorite cooking oil whether Olive or other.

Spread the grains out in the pan. Mix a bit with spatula then add the water. Sprinkle a bit of pink salt.

Transfer to an air tight container if storing. It holds it's quality even if you freeze it. (Good advice from Hiroko)
Reheat in microwave or rice cooker a few minutes.

I use Green Farm (Taiwan) brand, as I'm too lazy to make my own mix. Lol.
Pretty good mix of- Pearl Barley, Brown Rice, Millet, Oat, Black Rice, Sorghum, Lentils, Buck Wheat, Red Black Brown Wheat Meal, Rye and Sunflower Seeds.

Storage (uncooked): store in the Crisper section in it's original packaging, or any food grade bag with a zip seal. I also wrap it in a brown paper bag before I stick it in there. It's worked for me and doesn't grow molds easily. :)