First, choose area where bladderwrack seaweed is in an abundance, so not to deplete the population. Then choose bladderwrack seaweed which has fully inflated bladders.
Cut the stem of the seaweed above the holdfasts with a knife.
Shake the seaweed to rid it of shells and rocks.
This is an example of the bladderwrack seaweed when it has moved onto a latter stage in its reproductive cycle. These can still be harvested; however the end product is not as good.
Lastly the fronds are separated from the bladders and then both parts are dried.
The fronds can be ground til fine and used as flavoring. The bladders can be eaten as is and are a tasty treat similar to popcorn.