The day after Thanksgiving is both the best shopping day of the year or the worst. Combine a store offering its lowest prices all year with a crowd of anxious, cash-strapped consumers who've been standing in line for many pre-dawn hours, and you're asking for trouble.

Last year, we saw how quickly things can get out of hand, when a Walmart customer was trampled to death in Valley Stream, New York, during a Black Friday sale. There isn't any hard data on the number of injuries on Black Friday, but sadly, that wasn't an isolated incident, even for Walmart: Shoppers at the retailer have been hurt in stampedes near Grand Rapids, Michigan; another in Columbus, Ohio, reportedly took an elbow to the face. Black Friday rarely seems to pass without some scuffle or incident.

Shoppers might be surprised to discover how much the stores plan for a smooth shopping day before November even arrives. Best Buy stages trial runs at most stores the Sunday before Thanksgiving, to help store managers make last-minute changes to traffic-flow and safety. In the drills, the store arranges its merchandise and aisles as it will for the following Friday, and then the "BlueShirt" employees line up outside as mock customers, before the doors suddenly open and employees flood the store.

Best Buy sees itself as an industry leader in preparing for orderly and safe Black Fridays in other ways, such as handing out tickets to customers in line for the hottest items. Tickets are also an element of crowd control at Toys R Us, which continues to "evaluate and strengthen" its Black Friday procedures until the big day. In its effort to ensure employees' and customers' safety, stores' senior managers and security staffs monitor the crowds. "If at any point in time we notice customers acting erratically or perceive that altercations could occur," a representative says, "we take swift and immediate action to correct the situation."

Some retailers hire outside help and increase the number of security guards. At the enormous Mall of America in Bloomington, Minnesota, roughly 120 security guards are on duty during Black Friday -- more than double the standard weekend security detail -- and this increased presence remains in place for the two weekends before Christmas. Best Buy even authorizes store managers to hire a police detail if they deem the extra security necessary.

Many retailers also implement a ticketing system for specific items to prevent a mad rush to enter the store. Store employees typically walk the line of shoppers, handing out tickets, an hour before the store opens; a store selling just 20 $49 Blu-Ray players distributes 20 tickets. Sears and Kmart representatives say the system makes it easier for customers to understand what to expect once the doors open. (Walmart and several other retailers did not comment on their safety and security plans for Black Friday 2009.)

But personal responsibility is as important as retailers' safety measures. Matthew Podowitz, cofounder of Safe Atlanta For Everyone and a certified Refuse To Be A Victim crime-prevention seminar instructor, provides pointers on safe shopping:

• Stay aware. In potentially risky situations, awareness can mean the difference between getting swept into a confrontation and escaping one.
• Look for warning signs. Mobs don't suddenly form on their own, Podowitz says; they're often triggered by the actions of a few individuals who may be belligerent toward an authority figure.
• Trust your intuition. If your gut tells you something isn't right, put some distance between yourself and the crowd.

You should also have a plan, Podowitz says. "Moving directly with or against the flow of a mob likely won't get you away from it," he says. "When planning for the worst, look for routes to one side or the other that you might be able to reach should a mob form in front of or behind you." Podowitz also recommends choosing a meet-up location, in case you're separated from your party, such as a nearby parking lot.

And one thing that's worth remembering: Black Friday is about getting good deals, which ideally should be fun. Be respectful to your fellow shoppers, and look out for everyone's safety. On Black Friday, a little kindness goes a long way.

Keep watching WalletPop for more information on making Black Friday a fun and, more importantly, a safe shopping day this year.

For more Black Friday coverage, check out our Black Friday Deals and other Black Friday 2009 news today.