If the device (ASA) is not purchased as a new device, the best practice is to wipe the old configurations.
Part A:These are the steps below:
Step 1: Erase the configuration of the ASA
CiscoASA# wr er
Reload the ASA without confirmation
CiscoASA# reload noconfirmation
step3:Now apply Cisco default configuration
Note: this is necessary to have a configuration in the flash memory since we have
cleared it previously
CiscoASA# config factory-default
Never do this in a production environment
save the configuration
Part B: To configure the cisco ASA using Cisco ASDM
Step 1: On your favourite web browser, run the management IP Address “https://10.10.1.1
Step 2: click on run Startup Wizard
Now you can configure the hostname, password, DHCP (if you wish to use it as a DHCP Server) etc.
Step 3: Enable Network Address Translation (NAT)/ Port Address Translation (PAT)
in order for the internal network to use you configured pupblic address.
Note: Private IP Address are not routable over the internet.
Step 4: Enable the ASDM logging.
This is option but very handy as it allows for troubleshooting when the need arises.
Step 5: I think for me its vital to enable the preview mode in order
to be able to view the configuration before deploying it.
Click on Tools
Click on prefences
select “preview commands before sending it to the device”