How to use keywords in your content?

Here we go, with a tutorial series beginning today, from Web Listings Inc.

Keywords are vital as regards website optimization; so you need to select the right keywords, for which some amount of research may also be done. But let's discuss keyword research elsewhere...
So, here are some basics about keyword usage:

• Use multiple keywords.
• While optimizing a page, choose keywords apt to that page.
• Make sure the keywords also appear in the page heading and subheadings.
• Use the keyword in the first paragraph of your content, but never artificially stuff it with keywords.
• Use keywords judiciously; keyword density in the entire body text area should better be 1.5% to 2% for a word that should rank high.
• Never overdo it with keywords; you'd end up being spammed. 
• Include the main keyword in the last paragraph of your content.
• Alt Tags and perhaps Comment Tags can also have keywords, but that won't be really decisive. 
• Hyperlink one or two of your main keywords, to highlight it for search engines. But once again, don't overdo it.