greet him, as you would any other questgiver, listen to the opening story, and choose the 'metal decorations' quest. he will send you out to collect chunks of metal from the metal golems of istaria, so he can make ornaments for gnomekindle trees.
i first tried to hunt nickel gols in aughendell, but quickly found out that they do not count for this quest. so, remembering that yukon specifically mentions silver and gold gols make the best ornaments, i went after the silver gols in the canyons outside of chiconis.
hunt down the required 50 chunks of metal and don't forget to collect the ornaments as well. ornaments are like presents and are used in the same way. you can check your quest journal, as usual, when you have the needed resources.
well, that's it for gnomekindle for this year!! come back next time, when we return to the last couple dragon trainers and then it's on to new stuff!! see ya then!