If part of your strategy of building links to your site using the directory links, especially the general link directories, you'll need to pay attention on some things:

First, it is important to do manually sign up on the link directories. Why? First you have complete control over the process of signing up, which means you'll see all the warnings and all the rules that need to fullfil to your link be accepted. Of course, you will be sure that your link is signed, but also you'll be able to create different variations of a description of your site. This is important because a large amount of content can sometimes be considered spam.

Next thing you need to pay attention to not overdo the number of signups. If you do manually submission essentially it is not possible, but automatic submission can sometimes create the impression of spam. Although the links in the directories are accepted in different time, and the time period can vary from immediately to a couple of weeks, it can happen for a short period of time to accumulate a lot of links, and if in coming period your site don't get new links it would became suspicious.

Of course, not all link directories are free (such as for example slbox.org is free directory), has a lot to those who must pay the registration link. Also, there are folders with the auction, where depending on the investment itself, which provides better position. I also note that all directories aren't for your site, although each link became well, if you receive the best quality than in the general directories, your link to sign up folders that are related to the area of your site.

To get started, I would recommend to your site subscribe to the free directory slbox.org.