I am a (very) active member of the site, yet I don't remember seeing the "event" for these achievements. I have seen people with these achievements, but I myself have no idea how to go about them.

So if one of you brilliant achievers could help me out, it would be great. Thanks! :)

This was a site event in...march? You had to dance with people via the forums like the love infection event in february. It seems like an event that will reoccur each year so you'll have to wait a while to participate :)

Oh my. I have no idea how I missed it. 0.0 Thanks tho!

You can buy trinkets on the shop search to use in the shop http://www.subeta.net/explore/masquerade.php?act=shop