Did you check up this online demo: http://demos.telerik.com/aspnet-ajax/calendar/examples/functionality/specialdays/defaultcs.aspx
If you like to style all days you could use custom skin as shown in the demo. Such a way all days will be styled.
Another way would be to use seven special days with Repeatable
set to "Week
". They will repeat every week, so you will cover all dates.
the Telerik team
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