Start with a random point. Pick the next point according to the following equations.
a = 10
b = 28
c = 8/3
dt = 0.01
xn+1 = xn + dt * a * (yn - xn)
yn+1 = yn + dt * (xn * (b - z) - yn)
zn+1 = zn + dt * (xn * yn - c * zn)
Iterate many times and draw lines between subsequent points.