Forget about a specific amount. No matter what amount you come up with, it just won't be accurate when you retire. Just keep doing the best, as often as possible. Fight to get out of "expensive" debt, which are things like credit cards. Mortgages can be considered expensive or inexpensive debt, depending on how they are structured. 30 year fixed mortgages are usually "inexpensive" debt. Variable mortgages with balloon payments are (what I consider) expensive debt. I wouldn't sign up for one of those unless I absolutely knew I was going to be moving/selling before the balloon payment was due.

People should be saving/investing the majority of their "extra" money for as many years as possible. If you start early, your next egg will eventually build up sufficient momentum to carry itself across the finish line.

With that being said, people should follow suggestions by people like Clark Howard on how to live within their means. There are a lot of simple things people can do to reduce the cost of living, and most aren't painful.