What can I do to quickly become a better orator? For example giving a public speech, a presentation before a crowd, etc. I'm looking for things I can do to ingrain good speaking practices as habits, especially simple and powerful techniques that I can incorporate into a daily routine.
Toastmasters International would be an organization that I'd consider seeing if there are chapters near you that would provide the feedback and practice to help advance your skills. Something else to consider is how best do you absorb information. Are you a visual learner? Would it prefer to hear the information rather than read it or see it? Would you prefer to feel and experience it first hand?
While practice is probably the top idea, a close second to my mind is to know your strengths and play to those. Some people may be better at presenting after doing a bunch of rehearsals to get down the flow of the presentation while others may not find that as useful and prefer to just wing it as their style. Marcus Buckingham would be a reference on strengths-based work that may be useful here.
Well, the real answer is practice - in your day job can you make presentations to team members? Why not volunteer to deliver talks, attend debating groups etc?
You can practice in front of a video camera and watch it back, but this does not give you the real time feedback and connection with an audience, so you do need to get out there and talk.
Practice is right. Maybe this little book can help you The Quick & Easy Way to Effective Speaking
Stage Time, Stage Time, Stage Time.
Practice is the key. Practice in front of an audience is better but practicing alone still works. If you search for a way to practice at home I would suggest Powerpoint-Karaoke.
Get a random deck of slides from slideshare.
Configure your computer to switch slides every 15 seconds.
Try to give a talk that relates to the slides on the screen. It's important to actually speak. Just thinking in your head isn't enough.
If you do this ten minutes per day you will improve massively as a public speaker.
If it becomes boring, you can include some bodymovement into the speech. Multitasking to do Tai Chi exercises while giving Powerpoint-Karaoke helps you to develop control of your body while speaking.
There is no substitute for practice. When it comes to speaking, there are in essence two types of practice: 1) actually talking and discussing, in groups and on stage, and 2) the practice you do before each speaking event.
The latter is invaluable, at least to me. I rehearse and refine my talking-points until I get them as close to the essence of what I want to say as possible.
When it comes to slides, less is more, and if I can give only one tip, it's don't use a lot of text - in fact, don't use text at all (almost). It's been proven over and over that text on a screen that mirrors what the speaker is saying is both ineffective and, well, boring. It also ties you to your slides which can be very limiting in case you want to switch subjects but can't because of a particular slide order or content.
If you are using slides as a backdrop for what you're saying, I'd recommend using images instead.
There is also good practice in watching other people present. You might not have the opportunity to see a lot of people in person, so in that case, watching TED sessions is a good way to learn (pay extra attention to the way the use (or don't use) slides).
I would whole-heartedly recommend the book "Confessions of a public speaker" (Amazon), from which I learned a whole lot.
Edit: I should note that there are different kinds of public speaking, and more often than not they fall into two groups: 1) public speaking at an event or social gathering, or 2) the repetition of facts or status-meetings at a workplace. My comments above refer to the first kind.