This tutorial currently doesn't include an installation guide. I hope to include one in the future but, in the meanwhile, there are plenty of good GT3 installation guides available on the Web:
Java User's Guide. The official installation guide from Globus. See Related Documents.
GT3 Quick Start. Redpaper written by an IBM team lead by Luis Ferreira.
From Zero to GT3. Written by Ian Stokes-Rees
Grid Install for Windows 2000 Platform. Written by Michael Schneider.