Once they're raging, I'm not sure.... probably just space and acceptance. So it's ok for them to have these feelings - not ok to be violent etc - and they're still loved, and some time to work it out. I try to remind myself that it's his emotion, not mine, I don't need to be upset abuot it. (much easier said than done, though!). Sometimes doing something really weird or funny does work well, too.

Otherwise, watching for triggers and avoiding them, as Mrs Nerd says.