As you know, Clan Wars was finally announced over the weekend. Though there was no blatant, blunt date set for the launch of Clash Royale's new mode, a couple of Tweets suggested it'd be coming alongside the Balance Update later today.
If you want to recruit your own clan, be aware there are rules to abide by. You need to include your clan trophy requirement as it's set in game, your clan name and tag, and refrain from spamming other recruitment with your own (but that's a given).
There's still limited information about Clan Wars as of yet, but if all goes according to plan we shouldn't have long to wait to experience it.