Hi.
I have this problem as well. How do you log onto iCloud from the iPhone?
A piece of Apple weirdness - you can't log into
http://www.iCloud.com from an iDevice. You have to access it via a PC or Mac browser. However, you can access your Apple account from your iDevice - and that's likely where the options are.
I actuallly used all 8 of the possible color-coded calendars - each for a different type of event. For example: To Do, Family Events, Medical, Travel, Birthdays, etc. I set "To Do" (in the Calendar's own settings) as the default one, but you can select aany color/calendar when creating an event.
Not only does this add some color to the calendar, it also makes it easy to find things - just turn off all but the events you want to search (ex: birthdays) and they become very easy to identify. When done, put the checks back by all the calendars. Pretty cool!