Njord is, in my experience, a very generous deity. He is often content enjoying whatever the other Gods are being offered, and he’s also often happy to share his offerings with any other deity. Still, He deserves His own dedicated offerings whenever he can get them.Offerings can be on a set schedule–say, once a month or once a quarter–but they can also be spontaneous; for example, as an offering for a gift given or a request made.
Here are some suggestions of things I have offered Him or think that He would enjoy being offered:
Food: Fish, seafood, and pork. (You can’t go wrong with pork with any of the Vanir deities.) Clam chowder with crusty bread. Herring and rye crackers. Also, one of the offerings I give him often are gold-foil-covered chocolate coins. You can also give chocolates made with sea salt or in the shape of seashells.
Drink: Dark beer; gin; vodka. Or, anything that you have available. Currently, I am giving him whatever variety of gin I have on hand, though in the past I had a dedicated bottle of Death’s Door gin for Him from a local distillery.)
Other offerings: Gold or gold-colored coins; beads, shells, spices; anything else than has been used/can be as currency. Also, loose tobacco or cigars, either smoked or not. Seashells; fishing gear; boats. Anchors are another key image with which I adorn his altar.