Communication is key in any relationship. Therefore, you should remember to keep in touch with the contacts in your network every once in a while. This is critical in strengthening your relationships, and possibly expanding your network. You could periodically say hello to each and offer to catch up with them in upcoming events if they are willing to attend. Social media is also another way to remain in touch with your network. You should try to have your contacts added as connects on LinkedIn. On LinkedIn, you could periodically send them messages, like their posts, or endorse their skills. This enables you to remain relevant to them and they will also keep you in mind just in case they have opportunities that may benefit you.