As an employee or manager, if you need change a current punch time (a time not yet recorded), click on the Punch and Edit Time button. This will allow you to specify a time to a current punch.
Otherwise if you need to edit a punch that was already recorded, click on the "I need to change something" button:
(If you don't see these options, your administrator doesn't allow changes. They have the ability to turn this feature on or off.)
Once you've clicked the "I need to change something button," you'll see your current time card, and you'll see an "Edit" button next to each time. Click it to request an edit. Depending on your settings, your manager or administrator may have to approve any changes.