If you want to acquire speaking skills, you need to teach yourself to employ good speaking habits at all times, whether you speak casually or formally.

Um: Filling gaps in your speaking with words like "um" and "er" or the combination "erm" is a very bad habit that many people are guilty of when speaking. They use these non-words to give them time to formulate the next part of their sentences - give them time to think about what they want to say next. There are two speaking skills that you can employ to overcome this problem. Firstly, think before you speak. This should be the number one rule when trying to find good speaking habits. Secondly, slow down - people often have to use these gap-fillers because they try and speak too fast - faster than their brains can process what they want to say.

Courtesy: One of the hardest speaking skills for many people to learn is the ability to interject at appropriate times when somebody else is speaking. This involves many factors. You need to be able to read the other person, and listen attentively to ensure that you do not miss any important cues. For example, it is important that you listen so that when somebody stops speaking to allow you to acknowledge what they have said, you are able to respond appropriately. You also need to learn this skill so that you do not interrupt the speaker when it is not appropriate to do so. Indeed, sometimes it is good to interrupt someone, but you need to learn when it is appropriate and when it is not.

Pitch: Learning the appropriate ways to adjust your pitch at specific points during your speech is one of the most vital speaking skills you will come across. Many people make the mistake of raising their pitch at the end of their sentences, losing credibility as they do so. You pitch needs to alter slightly at frequent points as you speak, as this will prevent a monotonous sound that bores your listeners. However, you cannot speak with large and abrupt variations in pitch, as this could have adverse effects on your listeners and on the impact of what you are trying to say. For instance, if you are trying to issue a command but your pitch goes up in the way that it would when telling a funny joke, your command will come across as silly and nobody will take you seriously. 

Apologizing: Some people feel the need to apologize as they begin to speak. Many people have probably made this mistake at some point in their lives, saying things like "Sorry if I'm wrong..." or in some way taking the credibility out of what they want to say before they have even said it. This is a defense mechanism that is not at all a good speaking habit, and one of the most important speaking skills is learning to avoid this bad habit when speaking. Your opinion is something that belongs to you and something that is unique to everyone, and for this there should be no need for you to apologize. Do not apologize, assert yourself, but do not be overly assertive, and you will earn the respect of those listening to you.

There are so many good speaking habits and just as many bad ones, and it is up to you to decide whether you will take the time to hone your speaking skills to employ good habits or contribute to the increasing number of people who have bad speaking habits.