All you need to say is simply ‘Yes’ or ‘No’; anything beyond this comes from the evil one. (Matthew 5:37 NIV)
Simply say yes.
Simply say no.
Whatever you choose to say, mean it. Back it up with action.
Before you say yes, make sure you can do it.
If you are not sure you can or if you are saying yes to please someone else- simply say no (and stick to it).
You don’t have to explain it or excuse it, just be ready to live with whichever one you choose to say.
Let your yes be yes and your no be no.