Don’t respond to pop-up windows.
Secure your home Wi-Fi network using WPA-2 with AES encryption settings. There’s a good tutorial on how to do that here.
Set your Web browser to auto-update to ensure that you’re running the most current version.
Know the signs
How do you know if you’ve been hacked? There may be some obvious signs. For example, you may start getting emails from your friends saying they received a strange message from your email address. Or your bank or credit card company might call you about some suspicious activity on your account. If you installed a mobile app with malware on your smartphone, you might find some unauthorized charges on your phone bill.
There are other, more subtle indicators. You may find new toolbars installed on your Web browser, or new software on your computer. Your computer may also start behaving strangely or slow to a crawl.
These are all signs that you might have been hacked.
I’ve been hacked. Now what?
If you have been hacked, the first thing you should do is reset your passwords. Iwan recommends starting with your email account, followed by your financial and other critical accounts. This is because password resets for all your other accounts are typically sent to your email.
If you’re locked out of your account or blocked from accessing it, many Web services have steps in place so you can get back in. For example, Facebook has a system where you can use a trusted source like a friend to take back your account. Search each service’s help section for specific instructions.
Speaking of friends, you should let your contacts know that you’ve been hacked, and report the issue to the site. Also, run a scan of your computer or mobile device using a trusted and up-to-date antivirus program.
In the case of identity theft, order a copy of your credit reports, and file an initial fraud alert with the three major credit bureaus: Equifax, Experian and TransUnion. Contact your local police and report the identity theft, and request new cards from your bank and credit card companies. You should also continue to monitor your monthly statements for any more unusual activity.
Unfortunately, there’s no way to completely eliminate the risk of hack attacks and other cyber crimes. But by taking some safeguards and arming yourself with the knowledge of what actions to take in the event of an attack, you can help better protect yourself and minimize damage.
http://recode.net/2014/09/11/what-to-do-if-youve-been-hacked-and-how-to-prevent-it/