I receive loose seeds (not in a "breeder pack"). I put them in those little 2-dram "concentrate" jars sold at the local smoke shop. Little clear glass jars about 1" diameter x 1" tall, air-tight. I put some white rice in the jar, enough to cover the bottom of the jar. I believe that acts as a desiccant, absorbing moisture inside the jar. At least stabilizing the humidity in the jar. I put those inside a plastic food container (Zip-lock, Gladware, etc.). I put that inside a brown paper bag to block the light.
I think the idea is to keep the moisture low, the temperature from varying too much (thus the container inside container) and dark. I've had mine stored for over 6 months and they germinate fine.