For me, I wasn't really happy with who I was at the time. I knew there was some ideal version of me that was better and I just wanted to figure out how to be that person. I thought I needed some honest introspection and self-evaluation to be able to try to change anything about that. I went through a bit of a meditation phase, but I don't think any specific angle of approach is all that important.
The most important thing is in the process was that I started to be more accepting of the person I am. I came in with the idea that I could better myself by changing who I was, but instead I just changed my attitude about who I was. I'm still just me. Being able to admit that you have this-or-that flaw, or that you're this way and not that way is where you start to repair your self-confidence and relieve your insecurities. When you start to fix that stuff you realize all the negative things that stemmed from them.