The Moon was the first clock. Before there were weeks, months or hourglasses, people counted time by what they could see in the sky: a whole lunation —from one new moon to the next— lasts 29 days, 12 hours and 44 minutes, and that is where our months come from, the word itself included. This calendar is the pocket version of that ancient clock.
At the top you have today's Moon drawn exactly as it stands: with its percentage of light, how many days old this lunation is, and the zodiac sign it is passing through. Below that, the whole month day by day, the four phases with their exact time, and the Moon's entry into each sign. You can walk through the months with the arrows: forward to plan something, back to understand why that particular night went the way it did.
The phases are not decoration, they are geometry. The Moon does not change shape; what changes is the angle we see it from as it goes round the Earth. When it sits between us and the Sun we cannot see it — new moon; when the Earth is the one in the middle, we see it whole — full moon. Everything else is the positions in between, which is why the thread of light grows from the right and fades from the left when you watch from the northern hemisphere.
As for what each phase is «for», tradition agrees on the essentials: a waxing Moon goes with what is beginning and what should increase, and a waning Moon goes with what is closing, being cut, being let go. That is why people sowed on a waxing moon and pruned on a waning one, and why some still cut their hair with one eye on the calendar. Take it as a rhythm to organise yourself by, not as a law: the Moon keeps the beat, the music is yours.
If you are curious about what the sky says about you, right next door are the daily horoscope, the zodiac sign compatibility and, if you are not sure of yours, the zodiac sign calculator.