At this talk, Sasha of BlissfulBabySleep focused on tips to help make travel with babies easier.
Sasha travelled a lot with her babies and advised the best thing we can do is create a routine and predictability at home for your infant/toddler that will translate so that we can travel. Ideally, your baby isn't dependent on one spot, person or thing to sleep, so you can have your routine anywhere, by keeping the same structure and routine. Of course, this isn't always simple as, especially with family ;) people will want you to make exceptions to the routine! It can be helpful to involve grandparents/aunts/uncles in your bedtime routine, eg. giving baby a bath, reading a book, etc. But, be secure and confident in knowing your baby best and what will work for you.
The bedtime routine eg. bath, change, book, song, etc. is so important because this is how the baby gets their cues that it's time to wind down and sleep for a long stretch. When they are older toddlers and children, these cues are going to make it much easier to settle down and sleep in a different situations because the routine can be the same.
Most important with time zone changes is keeping the same structure and rhythm of naps, even if they're in the stroller all day. Keeping this routine will also help get back into the usual pattern when you get home.
Just like you would do for yourself, make the environment they're sleeping in conducive to sleep. If you can minimize distractions, darken the room, put on white noise (apps are available on your phone if you don't have/can't bring a white noise machine), sleep will be easier and the baby will not be getting cues to wake up.
When it's impossible to keep your sleep routine the same, for example if you and the baby are attending a wedding, bring their pajamas, baby headphones and a carrier. Change them into their pjs, if it's loud put the headphones on them and pop them in the carrier. If you walk outside for a few minutes or are moving on the dance floor they will be able to fall asleep in the carrier and if it's their regular bedtime they will likely stay asleep. Because they are ready for bed you will have minimal disruption when you get back and have to transfer them to bed.
When planning for time zone changes of 3 hours or less just jump into the new time zone.
If the change is more than 3 hours you can just jump in, but you can also adjust on the plane. As soon as you're on the plane get into the new time zone in terms of when naps should happen. Ie. if it's 1pm on the new time zone and that's usually nap time, try to get your baby to nap.
As soon as it's daytime in the new time zone get outside into the daylight and spend as much time as possible outside so the daylight can help them regulate their bodies to the new time. If baby is awake at night your main strategy will be not to be up playing, keep it boring, stay in the dark. If you get up and play because it feels like daytime to them it will only delay the adaptation to the new time. Because they nap it generally doesn't take babies as long to adapt to a new time zone as it takes us!