To quickly sort, select the Sort A to Z / Z to A icons in the Sort & Filter group of the Data ribbon by clicking the arrow below the Sort & Filtering symbol in the Editing group of the Home ribbon. Sort Smallest to Largest and vice versa are the labels in Excel 2013.
To perform a more complex sort, go to the Home ribbon and select Custom Sort from the Editing group's arrow below the Sort & Filter button. This opens the Sort dialogue box that appears when you click the Sort symbol in the Sort & Filter group of the Data ribbon.