* Go to (and speak at) meetups involving technologies you work with. It's a great way to showcase your skills.
* Be charitable with your time. Be willing to meet people for coffee and provide free advice. These sort of meetings often directly or indirectly turn into work.
* Leave your company in good terms--they might use you as a contractor after you leave.
I would definitely recommend saving up 4-6 months of living expenses before quitting. It gives you some flexibility in setting your rate and selecting jobs.