I taught myself how to use a DSLR. Ok, maybe that's a lie. A friend of mine taught me how to get proper exposure using the aperture and shutter speed dials and I was good to go. Never used auto features. The only thing thing that was set to auto was the focusing. I love the flexibility from shooting manual from underexposing to overexposing whenever I felt like I needed to. For me, there were no real rules because I never learned them. I've never even heard of the Rule Of Thirds. I just felt if it looks good to me, then it's ok. But, as I did more research and looked at what the pros were doing, I learned that what I was doing has been such a big no-no. Too overexposed? Bad! Too underexposed? Bad! Not following the Rule of Thirds??? Really bad! I have a natural tendency to rebel against rules. At the same time, I understood why these things are bad and why people want to follow these rules. To rebel takes a lot of understanding of the rules and bold judgement on why you feel they don't apply to your image.
Following the rules can also get really stale and boring as hell because "they" do it. Me? I've been looking at many amazing photos on 500px and following the works of my favorite photographers like, Jeremy Cowart, Joe McNally, and Zack Arias. I've learned a ton of techniques from them and I highly encourage everyone else to also. But, I still do not follow the rules because I do not want to emulate their style or anyone else's style or the standards. Look at what everyone else is doing and ask "How can I do that differently?"
I do my own style. Create your own.