Pressing the Enter key inserts a line break and starts a new line; however, more than one blank line between lines of text tends to be unstable (it may not appear when the page is browsed).

The bottom line of the Composer toolbar offers some options for modifying text. There is a little window which allows you to select normal text, headers of various sizes, an address format, a list item. The next window offers a variety of fonts, but you will probably want to stick to a choice between "variable width" (the default, Times Roman), and Arial, which gives a nice sans-serif font which many browsers can read. The choice of font sizes corresponds to the choice of header sizes, basically.

The next few items are best used when text has already been typed. Highlight the text and you can

• choose a color for it in the little black window
• boldface it by clicking on the bold A
• italicize or underline it by clicking on the italic or underlined A
• get rid of colors, links, and all other attributes by clicking on the eraser-ed A
• make it into an unordered list (bullet list) or a numbered list by clicking on the relevant list icon (note: if you are generating list bullets you don't want, you can turn off the list by going up to the first window and changing "List Item" to "Normal."
• indent a paragraph or
• move it back to the left by clicking on the arrow icons
• Change the alignment (flush left, centered, or flush right) by using the last icon in the bottom row OR by using the Ctrl-L, Ctrl-E, Ctrl-R commands common in wordprocessing.
 

Formatting text on a webpage is different from formatting it on a paper page because the page can change size. To keep sections of text side by side, or in another constant alignment, use bullet lists or use tables.

To check your work, you can  browse the image (Preview icon). Every time you make a change in your work in the Composer, save it; then reload the page in the Browser to check your work.