The info I collected was from reading, advices and personal strong gut feelings I got. I may or may not edit more if I find more info on him! :)
Zodiac: Libra?
Herbs: Cinnamon, Red clover, Peony
Stones: onyx, Red jasper, Zircon, Orange garnet, pyrite, lava rocks, Bismuth, Sun stone, black tourmaline, hematite, Carnelian.
Colors: Red, black, white, brown, orange
Animals: Donkey and quail
Symbols: Anvil, Hammers and Tongs, Fire, Volcanoes, Axe.
Offerings to Hephaestus: Milk, Beer, Cider, Copper, Bronze, Gold, Iron, Nails, Bolts, beads, tools (can be related to stone working or sculpting) Handmade items that you make. Instruction guides (maybe one you used to put together something you really like!) lighting a cigar (or not), Incense, Simply lighting a candle. Rustic items (like nails or tools). Braces or stretch bandages (because of him being disabled, also I thought stretch bandages could be used because of my mom when her knee cap would act up and she didn’t have a knee brace!)
NOTE: Thanks to someone mentioning it to me! You could possibly use a tool box as a secret altar. Or to place on a altar for him! :)