Wi-Fi is one entry-point for hackers can use to get into your network without setting foot inside your building because wireless is much more open to eavesdroppers than wired networks, which means you have to be more diligent about security.

1. Change the Admin Password on your Routers Each wireless routers comes with a default password for easy initial access. These passwords are very easy to find on vendor support websites, and should therefore be changed immediately.

2. A firewall helps protect your PC by preventing unauthorised users from gaining access to your computer through the Internet or a network so install a Firewall.It acts as a barrier that check any information coming from the Internet or any network.

3. Disable DHCP (Dynamic Host Configuration Protocol) for a SOHO network with only a few computer consider disabling Dynamic Host Configuration Protocol on your router and assign IP addresses to your computers manually. 

On newer wireless routers, you can even restrict access to the router to specific MAC addresses.

4. Change the Default SSID Name (Service Set Identifier) and Turn off SSID Broadcast This will require your wireless client computers to manually enter the name of your (Service Set Identifier)  before they can connect to your network, its minimizing the damage from the casual user whose computer is configured to connect to available Service Set Identifier broadcast it finds. 

5. Replace WEP (Wired Equivalent Privacy) with WPA (Wi-Fi Protected Access) WEP is a security protocol that was designed to provide a wireless computer network with a level of security and privacy 

comparable to what is usually expected of a wired computer network. 

WEP (Wired Equivalent Privacy) is a very weak form of security that uses common 60 or 108 bit key shared among all of the devices on the network to encrypt the wireless data. 

Hackers can access tools freely available on the Internet that can crack a WEP (Wired Equivalent Privacy) key in as little as 10 to 15 minutes. 

Once the WEP key is cracked, the network traffic instantly turns into clear text – making it easy for the hacker to treat the network like any open network. 

WPA is a powerful, standards-based, interoperable security technology for wireless computer networks. 

WPA provides strong data protection by using 128bit encryption keys and dynamic session keys to ensure a wireless computer network's privacy and security.