1. Do not store in unlined steel containers.
2. keep the head space filled with dry Nitrogen.
3. Do not use heat to dry your fuel (Magnesol wash instead of water eliminates need for drying)
4. Do not expose to sunlight (use opaque staorage containers)
5. Drive the conversion reaction as close to total conversion as possible. (Pull glycerin off from time to time during the process)
6. Hydrogenate the BD to close double bonds.

Some of these are more practical than others for an individual, but they all work and in combination can greatly extend storage life.