Adding number to days in the calendar and adding them together.

I'm making a program that makes it so you can write a note to that day and adding income aswell as expenses for that day.
I've managed to make it so it saves the notes for the day. And the issue is that I don't know how to write the code so I can save the income and expenses to each day.
If you guys just could help me save them, and tell me how I can add them together in another form that would be great.

As I am pretty new to Visual Basic I can't really give much information except this:
-Everything is linked to a calendar so I can just press a date and example the text will be saved on that (I have completed this stage)
-I don't know how to save the numbers to each day
-The numbers represent money
-On a different form I will have it so I can see total income/expenses for the month

Tell me and I'll add you on skype or I can upload my files here on the forum.

In advance, thanks.

-ZviXx