One of the hardest things you can be forced to do is to speak with people who are hostile to you.
When speaking to people who are hostile to you, you need to create the impression in them that you respect them, but you don’t fear them.
Further, when speaking to people who are hostile to you, you need to genuinely understand their point of view, and communicate that understanding to them.
Further still, when speaking to people who are hostile to you, you need to be assertive: which means avoiding the temptation to either be aggressive or passive.
Much, of course, depends on the source of hostility in the situation. It could, for instance, be harmless hostility: like where you happen to be having a Gmail versus Yahoo Mail argument, with you arguing for Gmail.com advantages whilst the other people are against the motion. This sort of hostility (if it can be called that) is quite easy to deal with. But it is very different from the hostility in a scenario where you happen to be facing truly physically hostile people, in which case the approach has to be different. So you are advised to deal with hostile situations on a case by case basis, drawing on your knowledge to figure out what the best way to deal with the situation is.