Here are some tips ive came up with that i also use. Everyone knows submitting to directories gets you more backlinks and increases your SERPS. #1 If you have alot of free time on your hands and you can submit to directories yourself, come up with an organized list and start at the top. There are many all over DP directorycritic is the most notable. Everyday do about 20 and mark where you left off. #2 Take some time to research what keywords are the most relevant to your site to use for your submissions. Also come up with a detailed description and a title, Make sure the title and description arent too long. Avoid using too many keywords in your description. In general the best description should be between 150-250 chars. #3 Research says using different Anchor text will help your site, rather then submitted to 2000 using the same Anchor text. So try to rotate your Anchor text everyday, It doesnt hurt to use up to 5 different ones. #4 Avoid submitting to directories that have no follow turned on, this basically means you wont get any credit at all if your site is listed on their directory. #5 When selecting categories to submit to make sure your using the most relevant to your site, alot of directories will decline for this reason. Another reason they will decline is if your site isnt submitted to a deep category. For example a Car rental site submitted to "Travel" should be submitted to Travel>Transportation. #6 Make a seperate email account only for submissions, you will receive alot of emails from this and much easier to go through without deleting important emails. #7 Directory submissions is a job never finished, but this is a good thing for more backlinks. Everyday there are new directories opening, and paid ones becoming free. Even if you submit to 2000 free directories, one month later there will probaly be at least 200-300 ones not yet submitted to. #8 If you dont have alot of time like most webmasters you can also pay someone to do them for you at a reasonable rate. You can also check out my offers in my sig.
Great tips, although I do not agree with number 4. Some directories do send decent traffic, so I would pay for a submission review at a decently trafficked directory who uses no follow.