The basic information about arrival, transport and accommodation is prepared in a nice form by the Charles University and should be sent to you from the University international office. If that is not the case, you can find the information booklet here.
This booklet covers the essentials of your arrival, accommodation, residence permit and health insurance. A more detailed section about public transport systems can be found here.
If you applied for a dorm at Charles University, you will most likely be living at one of the following dorms: Hvězda, Větrník or Hostivař. In cooperation with the dorms, ESN CU Prague prepared a leaflet, which contains the most important information regarding your accommodation. You can find the leaflet for each dorm attached below: