You need to create an init script for the service called 'amportal' and put it in /etc/init.d. (set execute permissions on the script 'chmod a+x amportal')
Have a look at some of the scripts in there to get an idea.
A basic service script will have the following structure, something like
# chkconfig: 345 80 20
# description: This is my service amportal
case "$1" in
rm -f /var/lock/subsys/amportal
echo "Usage: service amportal start|stop"
(you need to define start and stop functions at a minimum, can also have restart etc)
Then you type
chkconfig --add amportal
to enable the service in runlevels 345 (change this in the init script as appropriate)
The 80 and 20 specify the start and stop priority for the service compared with other services, 80 starts after services <80 and 20 stops before services which are >20 (look in /etc/rc5.d, the start links are Snn***, the stop links are Knn***, they're executed in numeric order when the runlevel starts or stops)
Now you can just start and stop amportal using service amportal start / service amportal stop