I would say that yoga poses are good for conditioning and toning PC muscles. You can incorporate poses that stretch perineum area like Padmasana, Rajakapotasana etc. But, to actually train PC you need to do Kegels, simple kegels. Do them regularly but do not overtrain. Don't go too hard in one day. And, if it happens that you overtrain take 3-5 days off to let muscles restore.