This is most likely easier said than done for some, but I just believe I will not have a bad trip and that doing hallucinogens in general are good for me and my mind. By believing this, I have avoided many a bad trip and have been able to completely reverse negative feelings into a completely positive mindset (possibly more positive than if I had been happy/fearless from the onset)

As a medicine, hallucinogens are an amazing source of healing. If you believe deep down that you cannot be hurt and only healed through psychedelic revelation, than the chances of having a bad trip diminish (assuming a comfortable, safe setting and positive state of mind).

Taking deep breaths and meditation surely help before a trip as well (especially with DMT, where taking as deep of a hit as possible is helpful). take 8 deep breaths (as deep as you can) and hold them prior to smoking your DMT. turn off the lights and focus on a candle and clear all thoughts and fears, repeat to yourself that you are fine, you are safe, and let the DMT guide you.