What do you do when he makes a mistake? Well, I can tell you what not to do. Don't have a fit.
There are several things that go through a man's mind when he has made a mistake. He is mad at himself for making a mistake. He is embarrassed to have made a mistake in front of you. He is trying to figure out how to resolve the situation created by his mistake. He is, as modern people like to say, "under stress." So, are you part of his stress?
Wives, for some reason, seem to love to attack a man when he makes a mistake. I have never figured this one out because it is so obviously self-defeating. If a man is fixing something at home and breaks it or makes it worse, the wife, too often, adds to his stress. "I told you that you couldn't fix it," she will say. If he misses a turn, she will yell at him and keep at him about it. "Why didn't you turn back there? You know that's where you are supposed to turn. Now, we're going to be late. You are always going the wrong way." For every husband mistake, there are reams of wifely responses that make things worse.
Next time he makes a mistake (which will not be very long from now), think a minute. Your job, as a Christian and a wife, is not to make things worse. Things are already bad because he made a mistake, are you going to add to the stress or help resolve it? What does God say to you?
First, do you need to say much at all? He is already embarrassed. He knows he was wrong. Does he need you to tell him he was wrong? Sometimes, quiet is the best response: "When words are many, transgression is not lacking, but whoever restrains his lips is prudent." Pro. 10:19.
Second, do you need to speak rashly? Almost never. "There is one whose rash words are like sword thrusts, but the tongue of the wise brings healing." Pro. 12:18. We know the Excellent Wife is a wise wife ("she opens her mouth in wisdom"), so whatever she says should bring healing, not more hurt. After all, you are called to be gracious in your speech: "Let your speech always be gracious, seasoned with salt, so that you may know how you ought to answer each person." Col. 4:6. Think a minute.
Third, whatever you speak must be to edify, to build up, to strengthen him. "Let no corrupting talk come out of your mouths, but only such as is good for building up, as fits the occasion, that it may give grace to those who hear." Eph. 4:29. Overhearing conversations in public places shows how unusual this attitude is, as most people seem only to want to unload their feelings, not give grace to anyone else.
Finally, I know you may be angry. We can talk another time about why these things make you angry, which is a problem in itself, but you have no right to speak in anger. The word is quite clear: "But now you must put them all away: anger, wrath, malice, slander, and obscene talk from your mouth." Col. 3:8. You cannot speak in anger.
So he missed a turn. The question is what to do next and the answer is turn somewhere else or turn around. Yelling at him or abusing him or trying to make him seem small or using him to unload your anger is not the answer. So he broke something? The question is what to do next and reminding him of other things he has broken ("you always break everything") is not the answer.
Conversation is not about unloading your anger, your fear, or your bitterness, but about building up the person to whom you speak. Even your husband.