Mine needed doing, and OH took his chainsaw to it in early spring! He cut it back to about 18". Then I mulched and fed it, and it's growing back well now.

I know that some people say to burn it, but in our case, it was far too near the fence. It would go up like a rocket - I wouldn't risk it.

Do it in March, as Spritzhenry above suggests - if you live out in the wilds somewhere, you can just set fire to it - if you live in a built up area, this is usually against local bye laws and may be a hazard. Hack back with shears or similar, taking all the leaves off right back to the central stump, cut out at the base any flowered stems, rake out the central part of the stump. Clear up the mess. You will need protective clothing and preferably safety goggles or glasses.

Especially gloves and long sleeves - the leaves are so sharp! Bamboo's right - it made an awful mess, and I filled my barrow several times over.