improve doc/README

README

 On server
 ==============
 
-1. have a look at the variables in virt-install-debian and adapt to your liking
+at first please have a look at the variables in virt-install-debian and adapt to your liking
 
 # kick installation
 virt-install-debian
 
+export DOMAIN=srvXXX
+
 # login and create /root/.ssh
 # install curl (until its part of base install)
 
 # shutdown
-virsh shutdown domain
+virsh shutdown $DOMAIN
 
 # copy ssh-keys of admins into machine
-virt-copy-in -d domain authorized_keys /root/.ssh/
+virt-copy-in -d $DOMAIN authorized_keys /root/.ssh/
 
 # start again
-virsh start domain
+virsh start $DOMAIN
+
+# set domain to autostart
+virsh autostart $DOMAIN
 
 On your workstation (chef master node)
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