First of all, it's important to define your opening days and times: this function has a major impact on the information given in real time to your future customers (closed, soon to be open, imminent closure, etc.).
In the main menu, on the left, click on Description
On the centre screen, click on Timetables
For each day of the week, indicate whether you are:
open non-stop
open with a break
closed
Then indicate the times for each day
Case of different periods and opening times:
As your business is certainly subject to seasonal peaks, your timetables may differ from one period to another. In this case, you can also define different timetables for specific periods
At the bottom of the "current" timetables table, click on Add new timetables
Enter the start and end dates of the specific period
Enter your timetables for this period
Note: Within these timetables, you will be able to define precise times for your activities when, for example, you set fixed departure times. See how here