Asterisk mapping as client to sip provider

please suggest how to map asterisk server as client to other voip provider
i got username andpassword

have domain name too…
if any body can pass me related config …
for sip and exten file
thankx

Outgoing Settings:
Peer Details:

username=sip-username
type=peer
secret=sip-password
nat=auto
insecure=very
host=sip-server
fromuser=sip-username
fromdomain=sip-server
dtmfmode=rfc2833
disallow=all
allow=g729
allow=ilbc
allow=ulaw
allow=alaw

Incoming Settings:
USER Details

username=sip-username
type=user
secret=sip-password
nat=auto
insecure=very
host=sip-server
fromdomain=sip-server
dtmfmode=rfc2833
disallow=all
context=from-trunk
allow=g729
allow=ulaw
allow=alaw
allow=ilbc

REGISTRATION STRING

username:password@sipserver

thankx vinod.

althogh same config was there in sip file still i made the necessary changes suggested by u.please suggest necessary changes for extension file.

after reloading asterisk and entering register string even in ow registry.
its not shwing registry.

thankx and regards