You might also want to look into a good pair of compression socks.
Also, take a look at this page for a list of exercises you can do on the plane to keep your blood flowing.
I've found that "paying attention to my feet" helps keep them from swelling up in my shoes and makes them feel a bit less achey afterward.
These instructions will also help prevent DVT , incidentally.
Tighten your calves.
Flex your feet and raise your toes 15 times per set.
This will tighten your calf muscles and promote proper blood flow through your legs.
Turn your ankles.
With your feet off the floor, move one foot clockwise, the other, counterclockwise.
Repeat, only switch directions.
Lift your feet.
With your heels on the floor, raise your toes up; then lower them to the ground.
Then do the opposite — heels up, balls of your feet on the floor.
Roll those shoulders.
In one smooth circular move, raise your shoulders and bring them forward, then down, and then backward.
travel.stackexchange.com/users/None/
I find slip-on shoes more comfortable on inter-continental flights as it allows me to take them off if I feel like it, and it's easy to wear them again without feet feeling sore.
While I haven't used them, some people advocate wearing flight socks that prevent your feet and ankles from getting sore.
Most times when I fly with budget airlines though I don't have space to pack two pairs of shoes as I take only carry-on luggage.
In this case, I wear my running shoes, but ask for an aisle seat during check-in which gives so much more space to stretch my legs.
The same helps during long-haul flights too.
I also check up SeatGuru for crowd-sourced data on what seats are best on a particular type of aircraft / airline and then ask for those ones during check-in.
travel.stackexchange.com/users/108/Ankur Banerjee
I'm a fan of just taking off my shoes if I'm not wearing sandals.
travel.stackexchange.com/users/408/Daniel Schaffer
For a long flight I would always go with flip-flops.
When flying long distance carriers always provide a commodity bags where you can find some sockets.
So basically if you are scared of getting cold (because it is cold up there) you can just put them on.
In order to be polite, I go until boarding with regular shoes and once in the place switch them.
travel.stackexchange.com/users/180/Spredzy
I don't have room in my carryon for a set of shoes that are just for the airplane, so whatever I wear on the plane needs to also be what I wear in the airport.
There's a lot of walking
so it's vital
the shoes be comfortable - I choose them carefully.
Flat pumps work for me and they slip off on the plane if I want to tuck my feet up under me in my seat or just give them a bit of a rub.
Tieing and untieing shoelaces in the cramped confines of an airplane seat is a non-starter for me.
You can find pumps and get your feet into them even if you can't see them.
Whether or not the airline provides socks for you varies wildly.
SAA is the only one I've got socks from in economy.
Generally everyone gives them in business.
travel.stackexchange.com/users/46/Kate Gregory
Does anyone have recommendations for great shoes for a long flight?  I usually wear running shoes, but my feet often get very uncomfortable after a few hours.
Shoes for long flight
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<air-travel><long-haul><footwear>
travel.stackexchange.com/questions/898
travel.stackexchange.com/users/403/user403
To avoid discomfort on a long flight it is best to wear shoes that are easy to remove during your flight and to put back on before landing like slip-on shoes and flat pumps.Another option is to simply wear open shoes like flip-flops or sandals. However, Many people advocate wearing flight socks to prevent discomfort during their flight. To avoid discomfort on a long flight it is best to wear shoes that are easy to remove during your flight and to put back on before landing like slip-on shoes and flat pumps.Another option is to simply wear open shoes like flip-flops or sandals. However, Many people advocate wearing flight socks to prevent discomfort during their flight.
To avoid discomfort on a long flight it is best to wear shoes that are easy to remove during your flight and to put back on before landing like slip-on shoes and flat pumps.Another option is to simply wear open shoes like flip-flops or sandals.  Many people advocate wearing flight scks to prevent discomfort during their flight.