I want to print also teachers' names in timetable printout/ need bigger font size

font size, print,

You can customize what is printed on each card:
1. Go to Print - Print preview.
2. Use the right mouse button on the desired card:
3. Check what shall be printed:

The same aproach can be used to specify texts also in individual timetables.

You can also specify the font sizes and positions for each element that you want to print.

Remember that you are customizing only one type of the card. This allows you to use different layout/fontsizes for double lessons and different for single lessons. On the other hand, if you want the same settings on every type of cards, you can use Set for more button.