You will be able to edit the timetable after certain progress in the game. To do so, you need to unlock the research TIME MASTER. Remember that you could get these boosters by tapping on the test tube icon. 

 

Once you have unlocked Time Master, Philippe will show up and explain to you how the timetable works, and which activities you can choose.

 

Pay attention to him and don't miss a detail! If you couldn't listen to Philippe, you don't have to worry: you can tap on the help button in the lower part of the timetable window as many times as you need assistance.

 

**If your game seems to be stuck on the Time Master tutorial, please try to tap on the clock widget (timetable button). The team knows about this small inconvenience and will fix it in the next version of the game.