If you haven’t installed the latest hotfix for Citrix Provisioning Services 6.1 yet (be ashamed 
). But not to worry when you are working with version 5.6 (or lower, again be ashamed…) you can upgrade your PVS server directly to PVS 6.1 with HF1. You do not need to install PVS 6.1 and then install HF1 over this installation. As the HF1 is a complete installation of your PVS software you can directly upgrade to this version.
For the target side you can install the target device software and copy a few files manually (when having the vDisk in maintenance mode) and your done.
You can read more about the patch here or see the installation step-by-step guide here.