Now, I have only just started paying attention to holidays as for as deving for them, and even then it is usually only the holidays I like, but yea…
My point is that you should always pay attention to the next up coming real life holiday so that you can dev for it on IMVU.
Some devs believe two weeks before the holiday is fine, while others believe right after the current holiday has passed you should start on another, but me personally I believe for the most part anytime before the holiday is fine. All you really have to do is make sure to add the right holiday tag to your item and people will be able to find it be it a year ago or two months ago. Like for example I wanted people to see my Halloween stuff, but I made it so early that no one even sees it on the first 5 pages of my catalog; well, no problem just search your own catalog for Halloween and share the link that looks like:
Except, that link can get a little long, so feel free to use a url shortner site to shorten the link for people if you want.
I started Halloween a bit early to be honest, so yea, these are my Halloween products: