First of all you can have a look onto this web page (also this web page http://www.apc.univ-paris7.fr/APCMediaWiki/UtiliserGap -in french-, merci Tristan).
I give here some useful  commands to submit jobs onto the grid.

voms-proxy-init -valid=1000:00 –voms superbvo.org

WMS: Workload Management System
Definition of WMS took from Italian Grid Page
The Workload Management System (WMS) is a software subsystem of the gLite suite which [...]