Pay for weekly expenses in cash. For example, I set a 50$ a week entertainment budget, which I carry in cash. That helps keep me to it.
DO cancel cable, TV is worthless for the most part. If theres a show you want to watch,go hangout at a friends house and watch it, or download it.
Agree about the cell phone thing. Seriously, data plans are a huge expense and more of a creature comfort than anything. I am sure you can go a few hours without tweeting.
Dont Buy or Rent too expensive because of the image of it. McMansions will not appreciate in value.
Buy a car that you can pay for all of, or most of with cash. If you do have a payment, pay it off as soon as possible. Once I finished my car payments (early, mind you) I started seeing a nice increase in my bank account.
I agree with the save 20%+ rule. I have auto transfers from checking to saving for this. Easy.
Ride a bike if you can, or walk places.
Ditch the fancy gym membership.
Pay off student loans ASAP.
Get a second job moonlighting.