I'm still having lots of trouble trying to get my icloud to sync to my iphone 5s. Some times it works and I don't know how, and other times it doesn't. i added some stuff to calendar in icloud yesterday. and I still don't see it on my iphone 5S
OK, so you add a Calendar event at iCloud.com, but it doesn't appear on your iPhone?
If you create/edit a Calendar event on your iPhone, does it appear at iCloud.com?
Try to Refresh your Calendars:
On your iPhone, open the Calendar app, tap on the Calendar button at the bottom of the screen, and swipe down across the calendar list (you should see a spinning gear).
Have you been getting any pop-up requests (on the iPhone) to sign into iCloud?
Is it possible you're not using Cellular data for Calendars or other iCloud functions (go to Settings > Cellular and look through the list of apps)?