first take a gram or 2 aside for immediate use, then put the rest in a sandwhich bag, wrap that up in plastic cling wrap, wrap it tight and use insane amounts of wrap, take another sandwhich bag, spray it with deoderant and put ure weed in there, should be smell proof enough

also big glass jars with metal lids may also work, i know it works pretty well with small quantities, not sure bout larger quantities though.....