Below is a short note for enabling the HTTP server, configuring a local AAA admin user, and assigning a management IP on VLAN 101.
# Enable HTTP server for web management
http server enable
# Bind HTTP service to VLANIF 101 as the management interface
http server-source -i vlan 101
# Create a local AAA admin user
aaa
local-user admin password irreversible-cipher Sim@local # Set encrypted password
local-user admin privilege level 15 # Full privilege
local-user admin service-type http ssh terminal # Allow HTTP/SSH/Console login
quit
# Create VLAN 101 (if not existing)
vlan 101
quit
# Configure management IP for VLAN 101
interface Vlanif 101
ip address 172.20.0.5 255.255.255.0 # Management IP
quit