Can you feel the energy of people around you? Of animals? Kids? Every living thing has energy surrounding them and within them.
Being around people who are low on energy will be egotistical, selfish, dramatic. They focus on outside influences instead of their own.
So how does one know what kind of energy they are projecting? It all stems from within, are your thoughts and feelings aligned?
How you treat yourself and others will reflect what kinds of energy you have and how contagious it is. When one focuses on the love and gratitude of all beings, one is known to have high energy, a self-awareness of sorts. You can be assertive and develop mindfulness any time of day.