There are wonderful insulin carriers that can keep your insulin cool for at least 24 hours while traveling or on the go. Do make sure that you don't sit still during a long trip. Get up and stretch, walk around and if you in a car or bus, get out when you can and get that circulation going. If you are traveling by air remember to order special meals. Don't order low-carb meals as they may be too low in calories.
Some people are concerned about sending their insulin through the X-ray machines at the airport.
The ADA says that this is rarely a problem, but if you have a problem with this, ask to have it hand inspected. If you inject insulin on a plane, do understand that you in a pressurized environment and you will have to be careful when measuring your insulin. Don't take your insulin, until you see your meal being placed down in front of you. With a special order you may be first or last to be served. Take your blood glucose levels frequently to make sure that you are in control.