By now you know how to toss the I Ching coins to create a hexagram that will draw on ancient wisdom that's in synchronicity with your own intuition. But the next question is, why are the "odds" so important when it comes to I Ching, and how do they break down?
It's complicated, but it's also pretty simple. First, each time the coins are tossed they generate a single line, so it takes six tosses of the coins to generate the six lines of a hexagram. When each coin lands, it faces either up (Yin) or down (Yang), and there are eight different ways that three coins can turn up when you toss them.
For example, one of the eight possible combinations is three heads and another is three tails (there are three possible ways to get two heads and a tail, and three possible ways to get two tails and a head). When you get three of a kind, it is considered a "changing line." Obviously, the odds are against this.
Statistically, three heads (or three tails) is going to happen 1/8 of the time. Added together (1/8 X 2 = 1/4 -- remember your fractions? This means that on average you can expect to get one or two changing lines of either type whenever you toss the I Ching. If you get no changing lines that is somewhat exceptional, and can be interpreted to indicate that the situation or relationship you asked about is fairly stable for the time being.
In summary, using the I Ching three-coin toss method, your odds of getting a static Yang line are 3/8, a static Yin line 3/8, a changing Yang 1/8, and a changing Yin 1/8. Go ahead and try your odds now!