Step-by-step on-site guide: learn how to plan, mark, support, and install cable trays correctly, from shop drawing approval to final checks. But before you lay the first tray or clamp down a single cable, you need a solid plan. This guide breaks down the process step by step. Mark the cable tray. Method Statement installation of Cable Trays and Ladders - Planning Engineer FZE. The method gives details of how the work will be carried out and what health and safety issues and controls that.