Do NOT put 1x1 pixel images with links within your site. This does not help. Use the standard text navigation bar with your keywords as the link text. Text links are readily accepted and preferred.
Another "do not" is using text in the same color as the background color. This gets you a one-way ticket to Banned City.
Do not use your keywords over and over in a nonsensical manner. Directories definitely will not use your site and search engines have algorithms that weigh word use within certain word count specifications.
Do not use a search engine submission service that submits your site to hundreds or thousands of engines. Most people only use the top engines and most traffic is generated by the top 10 engines and directories. The second point to submission services is that the submission process is usually handled by automated software which is another ticket to Banned City. Search engines seek to block those companies using automated software submissions and are regularly successful at doing so. Submission companies are viewed as search engine spammers because they use the software to send in monthly, weekly, and even daily URL submissions that are not necessary - thus using precious resources and bandwidth. Bottom line - don't use automated software for submissions nor pay a submission company to do this for you.