Freeze your credit

TL;DR

WHO: Everyone
WHAT: Freeze your credit reports & setup monitoring
WHEN: Yesterday
WHERE: Experian, Equifax, TransUnion
WHY: It can can prevent credit fraud 

Long version

Experian defines credit fraud as "the criminal use of someone else's personal credentials, as well as their credit standing, to borrow money or use credit cards to purchase goods or services with no intention of repaying the debt."

Freezing your credit cannot stop the purchase of goods or services with a stolen credit card, however it can prevent nefarious people from opening new lines of credit in your name in identity theft scenarios. Since it takes less than 30 minutes to setup it is certainly worth it It is free freeze and free to unfreeze. The three step process is as follows 

1. Create an account at Experian, Equifax, and TransUnion
   It is imperative you create three unique passwords here, do not reuse these passwords anywhere else, Even if you normally reuse passwords. When one of the websites you use inevitably gets hacked, the attackers that have access to your password will try to reuse your credentials on these sites in particular because they are well known and have financial incentive to do so.
   
   
2. Enable credit freeze
   Experian https://www.experian.com/freeze/center.html
   Equifax https://www.equifax.com/personal/credit-report-services/credit-freeze/
   TransUnion https://www.transunion.com/credit-freeze
   
   

   
   Keep in mind all three bureaus use the terminology "Freeze" and "Frozen" they may offer similar paid products called "Lock." those are not necessary. Freezes are free by law 

    
3. Sign up for credit monitoring
   There are too many services to name, if you already have a credit card it probably offers this as a perk, lines of credit will show up on all three of these reports, so it is ok to not monitor all three. Personally I use Experian and CreditKarma.  
   
   

Now whenever you actually need to open a new line of credit, you'll have to log in and unfreeze your credit file, or thaw it in which case it will automatically re-freeze after a period of time.