Slice

When you add an event, there is a tab called "Event Date" at the top of the editing window. Use this to set the time and day for your event, to set recurring events, etc. If you include a start time and end time in the publication date information the event will display correctly relative to other events on that day in both your site and the slice site.

You should try to put your event into the category that is the best fit for it. Categories in your site are mirrored in the slice.unc.edu site and events can be sorted by category. This makes it easier for people to find your event among the others that are out there.