If you’ve gotten into the habit of typing all lower case or worse, all upper case, you really should break this habit. Using mixed case when touch typing is grammatically correct, and gives your typed material a more polished and professional look. Even casual typists should do this. Capital letters should always be used at the beginning of each new sentence or question. Capital letters should also be used with abbreviations and acronyms, proper names and titles, the days of the week and months, cities and countries, movie, poem, song and book titles, and some brand names. There are other examples of capitalization usage, but these are the most common.
When typing, letters appear in lower case by default. If there is a situation where you need to type a series of upper case letters, you simply toggle the [Caps Lock] key on and off as needed. On a QWERTY keyboard, the [Caps Lock] key is located to the left of the letter A. Press once to turn [Caps Lock] on and all of the letters you type will be capitalized. Press the [Caps Lock] key again to turn this feature off.
However, when you only want to capitalize a single letter, or the first letter of a word, the [Shift] key is more appropriate. The [Shift] key also serves another purpose. Looking at the keyboard, you’ll see that most non-letter keys have dual purposes. For example, above the number 1 is an exclamation point, and a colon is above the semicolon. When you need to type an exclamation point, colon, or any of the other symbols or punctuation marks on the top of these dual purpose keys, you must also press the [Shift] key.
You’ll notice there are two [Shift] keys on the Bottom Row of the keyboard. One is to the left of the Z key and the other is to the right of the slash/question mark key. When touch typing, you press the [Shift] key with the little finger of the hand that is on the opposite side of the keyboard from the key you need.
In other words, to type an exclamation point, you will press and hold down the [Shift] key with your right-hand little finger while you press the exclamation point with your left-hand little finger. While this happens, your other fingers should remain on the appropriate home row keys.