Create an account in Twitter or Facebook then add people that can be your customers. In twitter it is not like adding friends in Facebook. You'll follow people and in return they will follow you too. Your followers will be ones that will receive your post messages. You can twit your products there. Offer it to your followers.

Twitter and facebook are only used to get traffic and it is a very good method for increasing the sales of a website.

You can use them in promoting your site, you can put your link on your profile and send a message on friends about your site.

Guys, thank you very much!

@limochicago, yeah I've accounts over FB and twitter already. But not fan pages at FB yet.

@paulgl, thank you very much for explaining it.

Utilize Facebook and Twitter to create a following or fan group by providing informative, relevant information. If they like what they see and read, they'll continue to visit--plus, visit your website. Hope this helps...Good luck!

It is possible to get a dofollow link from facebook

@SEOArbiter, Thanks for the advice.

@Preciseim, are you sure that facebook really offers a dofollow link? I've heard that they are nofollow.

They are no follow but I believe, twitter links have effects.

I normally tweeting my link to one of my accounts then auto retweet to around hundred more accounts. Of course they are coming from the same IP which means the volume have no much effect.

But if your links was retweeted by many other twitter users, the tweet that contains your link will be listed in hundreds of tweet\retweet statistic sites. Which means you get tons of backlinks from high PR sites.

@jayanuaria, I don't understand about what you said like "tweet once and retweet it from 100s of other accounts automatically". Is it allowed in twitter to have this much accounts for a single person? Won't they ban such activities?

Direct links from status updates to your websites on social media sites such as Facebook and Twitter are always no-follow. That said, there are a couple of ways of leveraging social media sites to generate traffic via indirect methods as follows:

* Submit your Twitter timeline feed to the RSS directories

* Submit your Facebook status feed to the RSS directories

* Get your updates on "re-tweeted" on Twitter and "liked" on Facebook as there are a number of social search engines (tweetmeme, etc.) that scrape social media sites and display results directly on their sites. Some of these result in do-follow links directly to your site and this can increase your site's PR over time. This can be done by effective use of re-tweet and share buttons on your own sites, blogs, etc. and by setting up retweet/share giveaways to your followers and friends.

* Submit your social media profiles to social directories (twellow, etc.) and these may also generate traffic back to your website over time.

Social media pages are like any other, but with the built-in benefit of residing on a very powerful domain.
Use Facebook's "about" box for relevant content and keyword-rich descriptions.
The first 40 characters in a tweet are what appears on a search engine; use them wisely.
Create a custom Twitter background showing links to your other social media pages.

Basically there are two ways to get search engine traffic. The first is to pay for it via pay-per-click advertising, and the second is to earn the traffic with optimal search engine placement. In the earned search marketing business of search engine optimization (SEO), a Facebook fan page is merely a web page, just like any other, except that it has the built-in benefit of residing on a very powerful domain. The same goes for YouTube, Twitter, and LinkedIn. Smart optimization, combined with the strong domains that house them, can propel your social media pages to the top of search engine results for relevant searches.

SEO can be broken down into architecture (the way a page is built), content (what appears on the page), and linking (inbound hyperlinks from external sources). Since most social media sites give very little control over the architecture of the page, you will usually be left with linking and content as the only elements that can be changed.

1. Provide regular updates. Like most social media, a Facebook page is only as good as the content available for fans to interact with. Generally speaking, the more digital assets (videos, photos, etc.) the better. Provide regular updates (at least daily and preferably more, though this will depend on your niche) that encourage user participation. Respond to user feedback. To keep from falling behind, consider creating a calendar of updates at the beginning of each week or month.

2. Choose a good name for the page. The name of your Facebook page is arguably the most important early decision you will make because this is the very first thing the search engines will see when they visit your page. At the very least, you should include the name of the business. You might also include targeted keywords if appropriate.

3. Choose a good username. A username allows you to have a "clean" URL. For example, if you choose (its mine) "thepokerprincess" as your username, your page URL will be www.facebook.com/thepokerprincess These URLs look nicer on business cards and letterhead, and they are easier to remember.

4. Take advantage of the "about" box. The "about" box is a great place to include relevant content and keyword-rich descriptions. This is one of the only places on a page's "wall" that allows for fully customized copy to be written. Many pages use this space to simply provide a link back to the corporate website or place their tagline, but it is an ideal place to help the search engines understand more about your page.

5. Customize your page. For example, you have a large degree of control over how your tabs appear. In addition to adding unique content inside "boxes," you can frame a page hosted elsewhere, which allows for full control over the look and feel of that particular tab (within the confines of the Facebook page that surrounds it, of course).

If you have done press releases and you think it is not enough then you can simply make a fan page. There is a low conversion rates on fans on this kind of advertising but at least there are. In twitter, try to garner interested followers to make sure it will convert for you. But it will be hard to know which ones are good customers and which are not.

All I have ever seen is "spammy" or products that promote "spammy" behavior.

I think it completely depends on the audience you are targeting - Facebook has an advert option (costs but not much) which will automatically target users that it thinks it should be targeting, e.g. I'm into music equipment so the majority of ads that appear on my Facebook interface are music/DJ equipment.
I can't really say I've used Twitter that much for SEO but I'm sure it has good uses depending on what audience you are targeting.