I think we can all say that most incorrect ball contact comes from not using the right club and trying to swing too hard. Learn your distances with your clubs for sure but never feel like you are going 100% at a shot. By believing you have enough club to get to your target your tempo, timing and ball contact should all be better. Also, understand and evaluate the conditions you are playing in. Cold days, into the wind shots or awkward lies all call for a less lofted club than under normal conditions. We all will make bad swings but I strive to make my students make correct decisions before their shots. That takes mental planning and belief in process which I think leads to confidence. Focus, take your time making your decisions and then trust the decision.
Good luck and be prepared for whatever the course and conditions may throw at you. Cheers!!