I haven't started a challenge, but I think the ones that I've participated in have mostly been advertised through word of mouth.
What kind of challenge were you looking to start?
I was thinking of starting a "League of Extraordinary Gentleman" challenge. The graphic novel combines several classic fictional characters from well known books. You can read a few of the classics and the graphic novel to see how they all come together.
I'm doing that now.
What do you think?
A bloggy friend puts her own 'League of Extraordinary Gentleman' twist on a Victorian Literature Challenge she is participating in this year.
Very appealing idea. It would definitely attract those readers who want to know more about characters and where the inspiration for a modern take came from-- Good luck with your challenge.
Whatever you do, don't be like me and not finish your own challenge. LOL.
Advertise it on your blog, Goodreads, here, A Novel Challenge. You'll find people to participate. I also found posting about it once a month as a reminder was helpful.