If you plan to leave the country, you need permission from a Wilson DSO. A Wilson DSO will verify that you are in status and then sign the last page of your I-20. You have six months to travel on that signature. Schedule an appointment with International Student & Scholar Services to get this signature. It takes one day or more for a DSO to make sure they can sign for travel, because the DSO must verify that you have been in-status the entire time. Again, plan for travel signatures ahead of time. Students on OPT also need a travel signature every six months.