So my theory is that every time you can get a sentence/word out fluently, you're building that fluent pathway in your brain. Every time you block on a sentence/word and try to force the words out using breathwork, block-n-hold, voluntary stuttering, easy onset, etc, you're actually reinforcing the disfluent pathway in your brain. So I'd do as much as I can to make sure when I speak, most of my speech comes out fluently--even that means having to imbue more emotions/animation/tonality into my words and taking on a new personality. Practice as much as you can talking with strangers, do Contacts on the streets, call up retail stores, do voice chats online, etc. Also voice every thought in your head out loud and make sure these thoughts are fluent when you voice them out. The more you talk and build up this fluent new personality, the more you're re-wiring the pathways in your brain for fluency rather than disfluency. Over time the fluent pathways are built, and then you can gradually reduce the emotions/animation imbued into your speech so it doesn't sound too dramatic or out of character.