Speak with people by providing them with choices. Always give them the freedom of choice. Deliver your argument in a way that sounds favorable to them.
But this needs a lot of ground-work to be done, and you should know what or with whom you are dealing.
Nobody likes to be told what needs to be done, while some do, not everyone. But almost everyone likes the freedom of choice, where their internal dialogues tell them what they want to choose.
So, if you want something to get done, give the power of choice to people and magically you will still get what you want. This works when you place the choices in an obvious way to show that the one you want to get done is the winner. If you make it as their choice, you will have very little work to do in negotiating, convincing them for the action to be taken. Works everywhere – at home, at work, in the world. Just know when to use it.