To make the daemon start every time you boot up, do this as root:
//EDIT: This next step is unnecessary:
# chmod +x /etc/rc.d/rc.wicd
Then add these lines to /etc/rc.d/rc.local
if [ -x /etc/rc.d/rc.wicd ]; then
. /etc/rc.d/rc.wicd start
You then can add wicd-client to your desktop environment's startup, if you don't want to have to start it yourself every time.