Low on cheerfulness, high on neurotisism. How to be happier?

On my personality test I've come out very low on cheerfulness and trust and very high on anxiety, vulnerability and anger. I can't say I'm too surprised.

Having accepted that this is the case, what sort of things can I do to maximise my own happiness? I haven't had major problems with depression for a long time, but life has consistently been a rather unpleasant struggle and I think these sorts of traits give me a good indication as to why.

I know that JP recommends countering high nurotisism by inducing conscientiousness and I do try to do that (I'm very high on conscientiousness in all areas 80%+).

Experiencing a little more cheer would be nice though.