Every switch needs a hostname, VLANs created for each logical grouping, and ports assigned to the correct VLAN
These are the first commands typed on a new switch, before trunking or STP tuning are even relevant
All are entered through the Cisco IOS command-line interface (CLI), in the appropriate configuration mode

Command	Mode	Purpose
`hostname SW1`	Global config	Sets the switch's hostname to SW1
`vlan 10`	Global config	Creates VLAN 10 and enters VLAN configuration mode
`name SALES`	VLAN config	Names VLAN 10 “SALES”
`interface fastEthernet0/1`	Global config	Enters interface configuration mode for port Fa0/1
`switchport mode access`	Interface config	Sets the port as an access port (single VLAN)
`switchport access vlan 10`	Interface config	Assigns the port to VLAN 10
`show vlan brief`	Privileged EXEC	Verifies VLAN-to-port assignments

The same pattern – create the VLAN, then assign ports to it – applies whether you're configuring one port or a whole closet of switches.

What Is a Layer 2 Switch?