The opposite of shy is outgoing. Shy people are generally considered to be introverted and prefer to be alone, while outgoing people are extroverted and prefer social interaction.
If shyness implies an excess of awkwardness in social interactions, then to be the opposite of shy would be to act too trusting, with an excess of outgoing behavior. Most people are not entirely shy or entirely outgoing, but rather they fall somewhere between the two extremes. Psychologists and personality theorists disagree about whether people should be described as having a shy or outgoing personality, or if all people are both shy and outgoing in different circumstances.