Ginagirl is again, right as rain. What she said is what I would say.
Personally, I started with a tincture. Will never forget the day I tried it first. Took the recommended dose, a few minutes later went for a drive and was more than amazed, more like stunned, at how bright the taillights of autos in front of me, were. I got used to it so I don't notice it that dramatically, but nightvision especially is enhanced. And just overall eye integrity feels right.
Went from tincture to capsules, then as Ginagirl recommends, powder. The best would be of course to walk outside and pick some. Was in Wales awhile ago and saw them all over. Made me want to live there just for that.
I purchased some bulk powder from here and have been happy with it: