Matt Allen at WSP Civils made a quickstart manual for himself and other workers at his company that is very complete. The manual is tailored for the Leica D2000, Opera Duo and Ditchwitch equiupment but most of the steps are fundamental to all GPR systems.
GPR-SLICE Software Quickstart Manual - taken from a section in the main manual on the Subscribers Only page of the website.
Recommended reading for the background in GPR-SLICE Software and GPR technology:
(available on Amazon)
Selected projects from the workshop manual
GPR-SLICE Software - Quickstart introduction includes radargrams signal processing, time slice creation and3D volume creation 13min
GGGPR-SLICE Software Workshop Manual
*** Higly recommended introductory tutorial video on basic GPR-SLICE operations ***