I think most of people already knows about this. But I am just putting here for those who haven't tried!

Let me start from the main menu screen where you can background picture and time.<***Portrait mode to explain here. means you don't need to slide out the keypad.>
1. On your bottom screen, there should be 4 buttons. Press the right most one (looks like 4 dots).
2. Sub menus will show up. On the right hand side. There should be a long bar menu (Grey color for Rogers.) divided into 4 buttons. Press the third button from the top.
3. Now the sub menu will show <Audio & ring tunes> < Calendar> < ...etc
press the <Calendar>.
4. In default setting it shows the Monthly calendar. On top, it will say 'Month' . On its right, there's box shaped button. Press that.
5. Small menu will pop up. Now select Week View and Press the button.
6. Now the screen looks somewhat feels like time table... though someone might think, who has a schedule at 3 AM at the school?
7. Okay now click on the time slot that you want. Say Math101, 8AM to 10PM on Tuesday.(you may need small fingers to do that or use stylus pen)
8. New schedule menu will be shown. From here check start time and end time. Please change if you need to by pressing them and type with keypad( you can still do that with virtual keyboard too). And then scroll down to 'Subject' box. Press that and type in the subject name and bit of description such as room numbers, lab, lecture etc.
9. After that press save. Now the Calendar in Week mode looks different! The space for 8AM to 10PM on Tuesday is filled with Red (Rogers).
10. You can add more subjects by this way!
This method can be a bit of hassle but Once you record in, you don't have to waste your time to find where did you put your time table or log on to the system.
I hope this tip is useful for some people