How to Be Beheaded

If you're about to be beheaded, please don't be meek about it; that's unlikely to save you. Margaret Pole can be a role model:

She was dragged to the block and, as she refused to lay her head on it, was forced down. As she struggled, the inexperienced executioner's first blow made a gash in her shoulder rather than her neck. Ten additional blows were required to complete the execution. A probably apocryphal account states that she leapt from the block after the first clumsy blow and ran, pursued by the executioner, being struck several times before she died.

Alternative possibility: Have a bomb in your belly (ObSF: “If This Goes On…” by Robert Heinlein) set to go off if you're decapitated and your heart stops.