A quick google of 'how to clean a VCR' comes up with lots of illustrated articles on how to. So rather than create yet another tutorial, I'd suggest that. Generally, I'd use 99% or 91% Isopropyl alcohol and lint free swabs (NOT Q-Tips). Common 'Rubbing Alcohol' is only 70% Isopropyl (30% water) and doesn't evaporate cleanly. Also do not clean the drum with an up and down motion. Rather rotate it slowly and use the very minimal amount of pressure (use the least pressure that gets the job done on all the internal parts). As to what to clean, your best help is good workspace illumination and perhaps a magnifier. If it looks dirty, it probably is.