Nonstop flights are your best friend. More flights mean more waiting for takeoff, more waiting to deplane after landing, and more opportunities for delays and cancellations. If possible, start the trip-planning process by narrowing destinations with nonstop flight options.
You don't need to bring as much as you think. Unless you're traveling to a remote destination, remember that people raise children all over the world—you can purchase most essentials upon arrival. You also don't need to pack every toy. Ever give a child seven different toys only to watch them play with a random piece of mail? Lean into that when traveling. It's amazing what becomes entertainment when you're on the go.
Your main "going out" meal of the day is often better as lunch than dinner. That way, you can return to your accommodation and put the little one to bed on schedule. Getting takeout, decompressing, and planning the next day is often the best way to spend the evening.
Where you eat matters. Choose restaurants where you can easily get up and walk around if the baby fusses or a child needs to move. Avoid cramped spaces where tables are packed together or restaurants with a very quiet atmosphere. Outdoor dining is often the best option.
Ultimately, mindset is everything. You can prepare all you want, but confidence goes a long way. Be optimistic enough to believe you've got this and that things will work out, but flexible enough to adapt when they inevitably don't go exactly as planned.