1)Roast it on low to medium heat so it doesnt get burned.
2)Keep mixing when roasting
3)Always cool the coriander seeds before grinding.
4)Always cool the coriander powder before storing.
5)You can store this in a air tight container for over a month.
6)If you are making a large batch of coriander powder, store in fridge.
7)use dry spoons when take coriander powder from the container.