Don't walk across the runway as so many twats do.
I have crossed a fair few runways in my time and have therefore achieved full twattishness.
What I do is to stop, look and listen in both directions and then if safe to do so, cross briskly.
I have found it to be a much safer undertaking than crossing the road outside my house, even when not wearing a hi-vis jacket.
I have also been known to enter a runway in an aeroplane.