If your CoSchedule account is not connecting to your WordPress blog, try deactivating and reactivating your CoSchedule plugin to refresh your blog connection.
After reactivating, CoSchedule will bring up a sign-in window. Click Sign In With An Existing CoSchedule Account and enter your CoSchedule login information.
If your calendar has been previously connected to WordPress, it will automatically connect. Otherwise, after signing in, your calendar will be listed as an option.
If your calendar is not listed, or still does not connect properly, contact support.