to give yourself more space between paragraphs, use the paragraph code: <>
to put a break between lines, use the break code: <>
italics use <> before the word, then < / i > after the word
or bold use <> before the word, then < / b > after the word
or underline use <> before the word, then < / u > after the word
Here's some links to pages that tell you even more about HTML:
HTML Cheatsheet
Barebones Guide to HTML
If you're having trouble getting logged out by the system, try to open other people's blog pages in a new window: right click on link and select "Open in New Window"