Now we are looking at grammar "the principles or rules of an art, science, or technique " of communication. Everything on the language of what you say, from vocabulary, sentence structure to figures of speech, falls in this category.
One of my favorite examples of grammar as an effective tool is the question posed by Groucho Marx: "So, when did you stop beating your wife?"
Grammar is the easiest and hardest thing to effect in your speaking. You have a whole storehouse of grammatical patterns built into your everyday speech and thinking. If these consist of good habits, then life is good otherwise you have that much more work ahead of you. If you need to improve your use of words, your common figures of speech, you overall way of string words into sentences and thoughts, the good news is you have a lot of opportunities to do it - whenever you open your mouth. The bad news is you will need to break old habits, conscious of what you say and how whenever you open your mouth.
Lose bad habits
Look for easy things first - cuss words and outright obscenities first. Then look for otherwise over-used phrases "duh", "you know", "whatever". Listen to yourself carefully. For a real eye opener try a voice operated recorder - just carry it around in a pocket for a day or so. You'll listen and cringe. Kids are also helpful in pointing out some of these foibles.
Once you are attacking these verbal bad habits, they'll often cause you to fill in the spaces with other sounds - um's and ah's that you'll need to prevent lest they get added as another verbal twitch.
Try to replace bad habits with good habits, instead of always simply going cold turkey. For instance, replace "you know" with "do you understand?" This is a helpful feedback mechanism and it's long enough that you'll drop it when you don't need, just to save the effort.
Have a goal
As you conquer your bad habits - replacing bad habits with better habits, you'll slowly acquire a growing awareness of what you say, as you say it. At this point, you can start thinking ahead more easily, thinking about the goal, the reason your point of what you are saying.
Now you are integrating structure!