Essentials are things that sustain you. The stuff, activities and people that maintain your health and sanity. Some examples of essentials are food for nutrition, exercise for physical fitness and sufficient sleep for mental health.
Categories of essentials are similar with most people and yet, differ for each person. Some must have a beer every night, while others prefer tea. Or some prefer yoga in a community centre, while others play football with their neighbours.
In weathering life's storms, your essentials become your anchor. Essentials help maintain your physical fitness, emotional strength and mental wits as you search for your direction. It gives you the time needed to steer your way towards calmer shores.
All other things are non-essential. These are things that do not sustain you. For example, buying 10 dresses when you only needed one for an important dinner. Or going on a date with someone you're not interested in. Non-essentials are distractions and may cause you unnecessary stress or harm.
And so, identify what is most important to you. Write it out. Review it often. Then, eliminate everything else.