Potions come in small corked vials, often etched or color-coded for easy identification. Each fits neatly into a belt pouch or bandolier slot. Treat them as minor items for encumbrance purposes - light, but fragile. Breaking a potion in a fall or fire can be a fun narrative twist.
If a character takes a hard fall or suffers a heavy impact, the DN may call for a Probability Roll (TN 12) to see if the vial breaks. On a failure, the potion shatters or leaks away. Potions stored in padded cases, bandoliers, or reinforced pouches are generally safe and grant advantage on this check.