If your travel plans extend beyond your current IDP's validity period, renewing ahead of your trip keeps things simple.
Start the renewal process a few weeks before your document expires, especially if you're traveling during a busy season. You'll typically need your current, valid domestic driver's license and an updated photo to process a renewal.
If your name, address, or license number has changed since your last application, update those details as part of the renewal rather than after, since mismatched information can cause confusion when your document is checked abroad.
Keep a note of your document's issue and expiration dates in your travel calendar so you're never caught off guard mid-trip.