I have several suggestions that I’ve found useful. First of all, it’s good that you’re already thinking about this in advance. I would start a written list if all the things you need to take with you. That will help minimize or eliminate forgetting something important.
I start by keeping Murphy’s Law in mind that anything that can go wrong will go wrong. I’m traveling right now and the pump belt clip broke on day 1 of a 16 day trip. It’s not crucial but it is an inconvenience. Take along some backup equipment that you don’t use often. This includes a backup battery-cap that can break. You could also take along some long acting insulin so that you could revert to multiple daily injections if you lose access to your pump. You should do an MDI trial for a week or so to prepare for this option. That means bringing enough syringes for this option.
If you have an old pump that still works, bring it with you. You may also get a loaner from most pump companies but realize if you lose it you will likely have to pay for it.
Bring at least 1.5x the supplies you think you will need; 2x is better. If you bring the exact number needed (insulin, infusion sets, test strips, batteries), fate may intervene and cause you to lose or somehow use up more than you planned.
Always carry all your diabetes supplies with you in your hand carry luggage; do not put your supplies in your airline checked bags. If you have two hand-carry bags, split up your supplies so that if one is lost or stolen, you have enough supplies to get by for many days and allow you the time to replace what’s missing.
I like to carry my insulin in Frio sleeves so that the inulin will be somewhat protected from temperature extremes.
If you’re traveling to country that uses another language, learn how to say “diabetes, diabetic, and insulin” in the local language.
I would refuse to subject your pump to x-rays, either hand-carry luggage conveyor belt or the millimeter (naked) scanner. They’ll often tell you it won’t hurt the pump (and it may not) but most pump companies say to not expose their pump to x-rays. Opt for the hand pat-down instead.
My list is not comprehensive but should be a good start for your planning. Oh yeah, one more thing. Never trust any refrigerator during your travel with your insulin. Fridges supplied by hotels can easily freeze your insulin.
Good luck and have fun!
