I choose not to wear makeup on flights. I know one day I’ll be sitting next to George Clooney and regret this decision but it’s just better for my skin personally.
If you do wear makeup include a few makeup wipes or even a small cleansing oil if you can fit it to take the face off mid-flight.
Must-haves on a longer flight are lip balm, a good rich moisturiser or hydrating spray and hand sanitizer. The air-conditioning in flights literally robs your skin blind of moisture so treat your skin overdrive to compensate.