There are a lot of personal development videos and resources out there. Here are some of the best.
This video is an hour long (I've cut to the point where he starts talking to save you the precious time), but worth the watch for me. It helped me understand how the world would be a better place if we were to speak our mind, which for me often mean setting boundaries with family, friends, and at work.
If you're able to do this effectively, you will have more time to yourself, more respect for yourself, and you will get to where you need to go a lot faster