- Put your e-mail address in your name, so that people can easily contact you without having to send an invitation.
- Write recommendations for everyone with whom you have had a good work experience (even if it was short term).
- Join groups for your region, and professional areas.
- Put effort into building your profile into a de-facto resume, with details about your job experience and skills.
- Search for recruiters at employers you are interested in and contact them about opportunities.
Feel free to check out my own LinkedIn profile for an example. You can also read a more in-depth description of how I am using LinkedIn (and other tools) as part of my job search strategy.