The first thing is always making sure that it is 100% complete, including a detailed summary, links to your website and blog that utilize the appropriate anchor text, and include your additional skills that make you more marketable.
-Join groups that you and your prospective clients are interested in.
-Customize your LinkedIn page URL.
-Updating your status regularly.
-Make sure to invite your professional network to connect with you.
These are all great tactics that you should absolutely do, but I also want to point out a few additional strategies that you may want to consider.