1. How to Connect to Cisco ASA?
Although Cisco ASA by default ships with a configuration that already includes 2
preconfigured networks, (Outside networkand Inside network configured to
192.168.1.0 subnet with configured DHCP server), which provides an easy way for
establishing initial connection over Ethernet, there might be times when this method
is not suitable. (For example if you have done some configuration mistakes in the
past and can't access device via network or have a different network configuration
setup).
To connect to Cisco ASA firewall, and setup initial configuration, use a blue serial
console cable (sometime refereed as rollover cable with PC Terminal Adapter) that
came in the package with your device. Connect the serial port of console cable to
your RS232 DB9 serial port on your laptop or PC, and the other end of the cable
(RJ45) connect to the console port on the ASA. (The older cables have a grey network
to serial converter that plugs on the end.) For connection, use a communication
utility - terminal emulation program like HyperTerminal if using Windows, or
Minicom if using Linux. Also you can use programs like Putty, TeraTerm or some other
application that supports terminal emulation and local serial line connection.
Once initial connection setting on the Cisco ASA are successfully configured, protocols
such as telnet, SSH, or HTTP(s) web base connection can also be used to connect to
device.
For connecting over console port, use this serial line setting on the terminal
emulation program:
Console port settings
Parameters Value
Baud rate: 9600
Data bits: 8
Parity: None
Stop bits: 1

2. Flow control: none
USB to Serial Connector
If you don't have a serial port on your laptop, you can use a USB-to-serial converter
adapter with DB9 at the one and USB connector at the other end of the cable (like
the one on the picture below). For this you will have to install driver which adds
another COM (serial) port on your PC. This way you will be able to connect to console
port from laptop's USB interface. (The driver usually comes in package with
USB-to-serial converter, and installation is pretty simple.)
Steps to Connect to Cisco ASA
1. Connect a console port on the ASA to the serial port on Your laptop/PC with the
blue console cable. (If you don’t have a console port on your PC, use USB-to-serial
adapter connector, see above):

3. 2. Open terminal emulation program like HyperTerminal, TerraTerm or Putty, and
onnect to COM serial port on PC (port should be created automatically from the
driver):
3. On successful connection You should see ASA command line CLI prompt:

4. (From CLI You are able to do some basic and advanced ASA firewall configuration.)
ASDM Web Access Guide:
1. On the PC connected to the ASA, launch a web browser.
(Verify that Java and JavaScript are enabled in your web browser)
2. In the Address field, enter the following (default) URL: https://192.168.1.1/admin
3. Run Startup Wizard
(notice that by default username and password are not set so if you are connecting
for the first time, leave them empty)

5. More Cisco ASA Tips and Guides:
Cisco ASA 5520 Basic Configuration Guide
Site-to-Site IPSEC VPN between Two Cisco ASA 5520
Simple Steps to Connect a Remote Office to Cisco ASA 5510
How to Configure Cisco ASA 5505 Firewall?
How to Configure Cisco PIX Firewall?