What a good idea!! I’d love to live closer to the ocean so I could collect a few! 
@MeganB did a lot of studying on Irish Paganism and she worked with Brigid. See here: Offerings at Home and Pledges to Brigid 📚
Megan hasn’t been active in the forum lately as she’s working on her own projects. But I know she is a skillful crocheter and I understand that offerings to Brigid should be more practical than anything else. Knitting, crocheting, weaving, baking, or handiwork of any kind are a good idea. For example:
I would advise you to approach her with love and gentleness. Never be afraid! Brigid know what’s going on and it’s up to you to worship her as she deserves. Whatever you need to know, she’ll teach you and guide you. Even if she’s not right for you, she’ll let you know.
I think it’s a great sign in your path that you have found your deity! 
Keep at it! 