You can post a clickable link right on your Twitter profile under your username like on my Twitters seen on my Twitter profile (Moola Mails) or you can just post them in your tweets. I think that twitter is no follow so it won't pass any "links juice" on to your link but it can't hurt
As for Facebook, you can post a link in your updates or on a friends wall. Just make sure to do it with common sense. Don't go posting to all your friends wall with a duplicate cut and paste post with your link. Social network marketing like this has proven effective to many online promoters.
Best of luck with your online venture.