Vriem takes 336 days to complete a full rotation around the sun. As such, early in history, the elves devised a calendar that divided the days evenly across twelve months: three for each season. As such each month has 28 days in it, and each month always starts on the first day of the week.
Each day is made up of 24 hours. In places with a belltower it is often rung on the hour from dawn to dusk. However unless one is living in a large city with such a bell-tower, keeping track of time is a more difficult task.
There is thankfully a natural phenomenon that rural people often use to keep track of time. The geostationary moon Aerinite (commonly referred to as the Watcher) is orbited by a large asteroid, Trona. The asteroid takes roughly forty minutes to cross in front of the Aerinite moon and as such can be used to measure time. This is commonly referred to as “a passing”.
Similarly, to measure longer time-spans, the smaller moon Adularia (known commonly as the Traveler) is always full on the 13th and 27th of every month. As it takes two weeks to complete its orbit. Thus one can count weeks by noting the phase of Adularia.