This process will default any configurations you already have on the switch so you want to take a copy of the config first.
Connect with the serial cable to the Console port.
Set your serial port speed to 115200
Login:
username=cisco
password=cisco
The above are default values.
Run the following command at the prompt:
#menu
This will bring up the Switch Main Menu
Select -> System Mode -> Edit ->Hit Spacebar to toggle mode from Layer 2 to Layer 3 -> Save
*sometimes, depending on your terminal emulation, you may not be able to get to the 'Save' option. Hit Esc, when you are at the top most parameter.
Your switch will reboot after another prompt to which you answer yes.
There will be no IP address when the switch boots up.
Configure an IP address on the default VLAN 1 so you can http to the switch as follows:
Same process as above to bring up the menu, then
System Configuration Menu -> Ip Configuration -> IPv4 Address Configuration ->IPv4 Address Settings -> Edit ->
Enter the IP address for the switch
Eg.
IPv4 Address: 10.16.1.1
Subnet Mask: 255.255.255.0
Save
Now you can connect to any of the ethernet ports and then http://10.16.1.1