According to the NASA page about news and events related to the moon, the start of October, 2016 saw the moon enter a New Moon phase - where it is not visible, as explained on the site:
the new moon isn't visible, because it's between Earth and the sun, and the unlit side is facing Earth.
The 'unlit side' is often referred to as being the 'dark side' of the moon.
and as shown in the terribly-but-necessarily-not-to-scale diagram below:

Image source and further information: SEMS: Moon Phases
The lunar cycle is roughly 29 days (the approximate time between consecutive new moon cycles as an example). There are many online 'lunar calendars' are available, such as from Moon Connection.
However, it is just as easy to observe the lunar cycles throughout the nights (weather permitting) - when the lunar cycles are heading towards a 'new moon', then it will appear to be 'waning', 'waxing' refers to the image of the moon 'growing' towards a full moon. Examples of how the moon would appear is shown in the NASA image below:

(Image from the NASA page linked above) - the cycle progresses anti-clockwise in the diagram.