Well, start with small steps and slowly increase the effort. For a long lasting change you'll need three things: effort, time and most importantly consistency. If you are as lazy as I was few years ago then start by practicing for a stupidly small amount, like 1 min of practice for example. Why so small? because it's easy to do everyday, which is what we want the most at the beginning! Effort isn't the main thing when you start, it's building momentum and momentum builds motivation. What I found out is that for the most part motivation stems not from your desires, but from the very work that leads you to these desires. That feeling of joy when you realize that you're improving is the best motivator, trust me, The key is that you're going to do this everyday, thus easily making this a habit. Once you're used to the 1 min practice, proceed to increase that time by 1 minute and so on. You'll advance faster than you think, just keep doing it! Later you can implement your new speaking pace into the real world, but again take baby steps, speak like this with the people you're most comfortable with first and then strangers. One problem with this is that it'll take time and you'll get impacient, so you just have to trust the process and the results will come. Here's a TEDx [talk](https://www.youtube.com/watch?v=AdKUJxjn-R8&t=) that explains all of this much better. Best of luck!