I LOVE green tea!
I think the trick is to start drinking it very, very weak. Just dip the teabag in and out super-fast. Gradually you'll acquire a taste for it and you'll be able to leave the tea-bag in longer.
Aldi has a line of flavoured green tea which takes the edge off the bitterness. You can get lemon or vanilla flavoured. The vanilla would probably be easier to drink if you're not used to the taste of green tea.
You can find quite a few recipes out there which include green tea (like this one
). Maybe mixing it with other foods and/or drinks would help take the edge off.
And as Ali said, you could also try it in capsule or tablet form if you really cannot acquire a taste for it.