I believe freezer, in a film canistor. Should be good for 0-8mths max. Unthaw for couple days. This is whats in the books, there may be better ways though. Possibly canister inside vac-seal bag to prevent freezerburn. Bested when used asap though(more viable-better results, more pollination points). and are you refering as to how to collect it, because there are many?