Regular exercise and cutting out any stimulants (caffeine, sugar, alcohol) will help cut adrenaline. Also doing relaxation exercises and meditation helps too.
I would also cut out anything that raises your stress levels but serves no useful purpose ... for example, I don't listen to the news anymore and I only briefly look at it online. Most of the stories reported are bad news stories and only stress me further when I read them - and it doesn't improve my life any if I know what's going on in the world in terms of bad news stories.
Oxytocin is generated when making love, and also fostered in the bonds we have with others. So cultivating healthy loving supportive relationships helps with that one. If you don't have a partner (I don't) then seeking supportive community with others helps - avoid isolating oneself. If you work, good working relationships can also be helpful and supportive.
Basically I think it's about trying to get a good life balance.