As an almost weekly flier (curently in Warsaw airport), I can only give you this sage advice:
'The art of good travel is never having to break into a sweat'.
That's all you need to know....
As a former fairly frequent flier, not getting stressed was key, that inevitably means doing everything in plenty of time. Get there early, get to security as soon as you can, find out which departure gate you need as soon as you can....and relax.
I never minded watching the world go by, relax in cafes or occasionally a bar, but relax.