Read books and actively read them by making sure you understand what you've read and be aware of the author's sentence and paragraph structure. Copy(write) what you read by putting it in your own words. Do it over and over again and eventually, you'll improve your verbal skills. It's a slow process but that's what it takes.

Taking classes is not enough. It comes down to practice, practice and practice.

Also, keep a diary, it forces you to summarise your thoughts.

Interesting, I like this idea, I will try this. Thanks.

It is more comfortable to talk with people side by side than face to face. I have had lots of good conversations with people while carpooling or walking somewhere together.

My oldest son has output difficulties. Walking together while he does most of the talking has helped him enormously.

Most of the time, I enjoy listening to my son. If you can similarly find someone in your life who enjoys listening to you and doesn't mind acting as a sounding board, just having the time to practice can really help you hone this skill.

Join a community or corporate Toastmasters. The combination of prepared speech making, impromptu speaking challenges offered in every meeting called "Table Topics", and leadership skills development will be a cheap and efficient way for you to experiment and grow skills quickly. Also a safe place to stumble, fall, pick yourself back up and succeed with no career risks.

Thanks. This is great advice. I was part of a Toastmasters and the "Table Topics" were really challenging for me, but are exactly what I need to work on.

That's a great question. From my experience one way of getting better is go to workshops. During training you get knowledge and also feedback, often you work in groups and people are more open to giving honest feedback than in real situations.

Yes. I've been trying to improve this area for a while as well. Here's some things I've come up with. I'd really like to hear about other people's exercises / practices, etc. if they have any. Its hard to measure improvement though in a non-subjective way. So anyway here's what I've come up with up to now.

1. Grab a random topic, record yourself explaining it. Listen back to the recording. Try to notice anything that you don't like, for me this is awkward pauses, saying some words repeatedly such as "right" or "uhm" and in general not having a fluid and coherent flow of thoughts and phrasing.

2. Take a particular situational goal: i.e. convincing someone to do something, making a joke, acting out a scene in a film. Record yourself acting out the situation. Listen back and see if you were able to convince yourself, or you laughed at the joke or you could hear the emotion from the film scene. For me the craziest of these is telling a joke. Its amazing how much difference super slight pauses or minute changes in intonation can make. It can completely make or break a joke.

3. Teach classes or do presentations at meetups / group events. If you can record yourself and listen back to it afterwards. See if you can keep your own interest. Try to fix things you find annoying with yourself.

4. Find other people you find really impressive. For English, I think Ben Shapiro is one of the clearest, fast pace speakers on the planet. I also like the precision with which Sam Harris speaks, so I listen to these two a good bit and try to take the best from their speaking styles and incorporate it. The key is to actively listen to what they're saying and how they are saying it, trying to figure out the techniques.

In terms of measurement, be sure to save your recordings. Then you can listen to yourself at the end of every quarter or half-year and see if you can notice improvements. Also actually measure how many times you've put yourself in situations such as giving presentations, speeches, etc. That's another way to at least quantify your experience and whether or not you are giving yourself a chance to improve.

These are really good ideas, I'll give some of them a shot.

I routinely listen to Sam Harris, his explanations are amazingly clear and concise. It's quite impressive.