How would you go about securing a network?

"I have successfully done this before in past roles. To start, I always find out more about the network that I need to protect. For example, what devices are on it, how many users access it at a given time, what data is on it, and what is its routing method? Once I've learned more about it, I install a firewall that I then continually monitor. I also implement a policy whereby all employees must update their passwords at least every quarter. In some cases, I might even recommend two-factor authentication as well, which just provides more security. In addition, I maintain our anti-virus software by regularly updating it. For any employees who travel, I make sure there is a virtual private network (VPN) in place for them to use. Finally, I educate and frequently remind all employees to follow computer security best practices."