This is a very good video series explaining some basic errors that can be met while trying to engage in practical Daoist meditations.   The first video is a great summary even for experts. The best benefit however is for self-initiates and newbies who are often clueless where to begin and whether they can safely practice on their own. The answer to that is: it depends on many conditions chiefly involving health and the purity of mind, but being too sure of oneself can spell disaster.   Deviations are not fun and can take a long time to heal, yet very often we can witness on this forum also how people have casual disregard for their own well-being. As if they were completely immune to any shortcomings and mistakes, and as if mastery was attained with the snap of fingers!   It's good to be informed that these deviation conditions exist. Teacher who can observe and help you correct yourself before unwitting mistakes and errors escalate into sickness is baseline for great teaching skill.   Video 1:   Video 2:   Video 3:   Video 4:   Video 5: