LOL. Marmite is divisive within the UK. The main thing to remember if anyone is invited to try it, try a tiny, tiny amount. It's basically salt on salt, so if you like salt, try a slice of toast with butter and a very thin schmeer of Marmite, and you will be in heaven. Do not dip a teaspoon in the container and transfer to your mouth - you will be incapacitated for weeks and will never get over the experience. Some people think Vegemite, the Australian "version", is better; personally I think it's for wussies.
This is WAY too much:
This is about right: