Hi Geraldine,
The best thing to keep feet happy are great shoes! There is a big difference between a $75 and $150 pair of shoes. Many might disagree, but as someone who has suffered from bunions (poor choices in my younger years), elevating my shoe purchase has resulted in happy feet. For the shoes that are more difficult to fit, such as sneakers, I purchased the Good Feet system about a dozen years ago and are really happy with the insoles. Another helpful tip when traveling is at the end of a long walking day, elevate the feet above the head (for me, that means laying on the bed and putting my stockinged feet up on the wall). This helps to reduce swelling. If there's a tub in the room, consider soaking feet in cold water for a bit. Or even a combination of the two.
I just bought a pair of Fit Flop Lulu Adjustable Leather Sandals and love them. They have this wonderful footbed and arch support that is comfortable right out of the box. Plus, they're super lightweight!
I realize this is a lot more information than your original question and I hope something helps in your search!
Happy Travels!
https://www.goodfeet.com/
https://www.fitflop.com/us/en/shop/lulu-adjustable-leather-sandals-p-ES6#592