There is a comprehensive Starlink Guide for those preparing for an observing run - Preparing to Observe (Starlink document SG/10).
In this section some notes on what to be aware of prior to an observing run are given. In outline: to successfully extract and calibrate an échelle spectrum a complete set of reference frames should be obtained at the telescope.
You might want to refer to the more extensive discussion of CCD data calibration in: A User's guide to CCD Reductions with IRAF, the section entitled ``How Many and What Calibration Frames Do You Need?''
Introduction to Echelle Spectroscopy