Listen to a tango to hear ONE-two-THREE-four rhythm. The ONE and the THREE counts are the most important beats of the music. Listen for each major beat. Step in place to each major beat. Walk around room, hearing major beats. Walk clock and then counter-clockwise around the outside edge of the floor. This is called the line of dance or "la pista" (the flow) which helps dancers not run into each other. Argentine Tango is danced counterclockwise around the outside edge of the dance floor and "dance traffic" usually falls into the center of the room in lanes.
If you are a man, pull your partner toward you with your right hand behind her back. If you are a woman, place your left hand on your partner's upper arm just above his biceps and push against him. Both pull and push should be as gentle as you can make them and still remain firm.
Extend your other arm (the woman's right, the man's left), not letting your arm sink or float. Press lightly against your partner's hand. Walk in the line of dance with your partner, the man facing forward along the line of dance, the woman backward. Keep your head up and turned slightly to the side.
Start with left foot (leader) and take two in-line steps (your left foot is in line with your partner's right foot and your right foot is in line with your partner's left foot.) Follower should reach back from the hip and take big steps. The leader should shorten his steps as he walks forward. After two steps in-line, the leader lets his left foot drift slightly to the left. The leader continues walking forward, and back in-line with his left foot, then drift to the right with his right foot, stepping outside partner with his left foot.
Leader pauses after count 2 and changes weight to right foot, keeping follower on her left foot. Leader steps forward on step 3 with this left foot while follower also steps back with her left foot. On count 4, the leader steps forward with his right foot and holds this step into count 5. On count 5, the leader leads the follower to step and change weight, crossing her left foot over her right.