Word offers two different ways to set up tabs. The first is by using the ruler at the top of the page. If the ruler is not visible click on View and then check the box next to Ruler. Two rulers appear, one across the top and one down the left side of the page. All the way to the left of the top ruler and the top of the left ruler is a small box showing which tab is selected. You can change the tab selected by simply clicking on the box. The default is the left tab that looks like a small capital L. Click it once and the center tab appears; click again and the right tab, then the decimal, and then the bar tab. After the bar tab there are two additional symbols, the first of which will indent the first line of the paragraph and the second one will indent all but the first line of the paragraph.
When setting a tab, first select the tab you want to use. Once selected, point your cursor at the ruler on top and hold down your left mouse button. While holding down the mouse button, you will see a dotted guideline coming down the page to show you where your text will line up. Click on the ruler where you want to set your tab. (See image below.)
The other way to set tabs in Word is to go to the Page Layout tab then click on the arrow on the lower right corner of the Paragraph box to open the Paragraph window. At the bottom left corner click on the Tabs button to bring up the Tabs window. Here you can set multiple tabs and you also have the option of putting in leaders. There are several leaders to choose from: dotted line, dashed line or solid line. The dotted line could be used when creating a table of contents to connect the title to the page number. A solid line could be used for putting in lines when creating a form.
If you are starting a new document it is good to set your tabs before you begin. Do not be concerned if you're not absolutely sure they are in the right place. Tabs can always be added, deleted or moved if necessary. To make changes to tabs, first highlight the text that you want to change the tab for. Then you can either move the tab symbol on the ruler or go to the Tabs page to make your changes.
In the top part of the image you can see the ruler with the left, center, decimal and right tabs set and the dotted line that appears when setting a tab. The lower half of the image shows the text highlighted so that when the center tab was moved and three bar tabs (red circle shows bar tab) were added the tab changes only affected the highlighted text.