Self-reliance in this essay is not about taking care of the externals of life, such as food, shelter, and clothing. Instead, it is about the state of one's soul: Emerson strongly advocates for trusting one's inner promptings and following what they say about one's vocation in life.
Emerson states that a person should be a non-conformist as he embarks on life, not looking to do what is conventional or expected, but rather following what his soul dictates:
Trust thyself: every heart vibrates to that iron string. Accept the place the divine providence has found for you, the society of your contemporaries, the connection of events.
According to Emerson, each person is born with a destiny implanted in him by God and will be unhappy until he fulfills it. The essay thus argues in favor of individualism: society can impede this, so it is important to cultivate solitude to discern one's true path, then follow that path back into society:
What I must do is all that concerns me, not what the people think. This rule, equally arduous in actual and in intellectual life, may serve for the whole distinction between greatness and meanness. It is the harder, because you will always find those who think they know what is your duty better than you know it. It is easy in the world to live after the world’s opinion; it is easy in solitude to live after our own; but the great man is he who in the midst of the crowd keeps with perfect sweetness the independence of solitude.
One must be original and true to oneself in order to find true contentment in life. Non-conformity doesn't mean just doing whatever you feel like in some hippie-dippy way, but instead means discerning, beneath material gain or the easy way out, what you are meant to do in life and doing it, even it's hard and people criticize you. There is no other way to live to one's highest potential or to find peace:
Nothing can bring you peace but yourself. Nothing can bring you peace but the triumph of principles.