This is an example of a book with a very good title, but little else. The author appears to have done hardly any research, mostly tells you stuff any writer would know, and the good advice — much of it is very good — is obvious. For example, you should sleep well. Eat fruit and vegetables. Exercise. Take breaks while writing. There is one bit of advice he gives — and he’s passionate about this — you should self-publish your book, as he did. Basically because, well, you make more money because you get a higher percentage of sales. He neglects to say that (a) maybe books by traditional publishers actually sell more copies than self-published ones in most cases and you’re in partnership with a business that is also trying to make money from your book and (b) not everyone loves to do marketing. Other than emphasising that one should get up early and have a word count target, there’s pretty much nothing else to say about “self discipline for writers” or anyone else. Not recommended.