Basic configuration

Find the MAC address on the sticker on the bottom
Add a fixed address entry for it to the DHCP server
Reset configuration. Power AP down, find the "MODE" button near the Ethernet and power jacks, hold MODE button, apply power, wait for Ethernet LED to turn amber, release MODE button.
Point a web browser at the WAP's IP address (HTTP on port 80 for now. A factory reset turns off the HTTPS and SSH servers if they were on) and log in with the default user name and password. You should be prompted with a dialog asking for Level 15 access credentials.
In the SERVICES section of the menu on the left side of the web interface, go the the Telnet/SSH page. Disable telnet, enable Secure Shell, specify a host key length of 2048 bits, and hit the Apply button.
On the SERVICES -> HTTP configuration page, turn off the "Enable Standard (HTTP) Browsing" checkbox, turn on the "Enable Secure (HTTPS) Browsing" checkbox, and hit the Apply button. You will connect to the HTTPS server on the WAP now (https://... instead of http://...)

Aironet WAP