Dick,
If you ingest 600 -1800 mg of freeze dried bladderwrack per day with meals, you would be in range to get the benefit without the added work.
If it is the taste of bladderwrack is driving you to the tincture project, you can put the dried bladderwrack in gelatin capsules and spare the taste buds.
Weighing out on a scale that can handle grams or parts of an ounce and loading small quantities of powder into gelatin capsules is labor intensive, however.

Now if you really, really, want to make the tinctures, you have at least two options: steeping and filtering, or repeated filtering.
Basic steeping tincture technique is 1 pint of 90 proof vodka or gin to 1-4 ounces of herb. Steep them for two weeks and strain
out the herbs. (this goes for making liqueurs as well).
Filtering uses a cone-shaped parchment with the herbs inside. You keep pouring the alcohol over the herbs repeatedly until it's
strong enough to suit you. (And how would you want to do quality control between batches...that is a LOT of work.)
Also, the Fucus vesiculosis tincture I bought got murky with sediment and changed taste before I finished a 1 ounce bottle, so tight seals and storage in small
exquisitely clean brown (away from sunlight) bottles would also be a part of your basic equipment.

I prefer buying the freeze-dried capsules since the dosage is consistent, and that is more important to me than saving a few dollars.
Good luck!
Joan