No problem. :)
Not sure if I included it up on my list or not, but some UPG and PCPG I've read about Loki suggests he very much enjoys poems, short-versed stories, singing and other types of music someone may play. It's been suggested that most Jotunfolk in general are very into music as a form of offering, so there's that.
As he is a father to several, having things symbolic of his children might be worth looking into. Carving a wooden figurine of Fenrir, offering bone to represent Hel, snakeskin for Jormungandr, etc.
And, though it's a bit controversial in the Lokean community at times, he does occassionally enjoy a lighthearted prank or joke. Some lokeans offer acts of pranks and tricks in his name. I think if you do this, you shouldn't be a nuisance about it. There's a difference between a lighthearted joke and being a pain and annoying, you know?