How do i talk to someone who has an anger issue? any tips on keeping them calm?

Carefully....: It depends on the degree of the assumed anger issue and the topic. Worst case: don't! your safety is a priority. If there's no physical danger, just emotional, it can still be don't. But if it is a valuable relationship, be careful and safe too. There's no way you can keep them calm. Try to stay calm yourself , don't accuse, make "i" statements, be brief and prepared to leave if necessary.