User Form Input

I'd like to create a user form to update an item that has cleared. My excel workbook has a sheet labeled "data" that is broken into Months, and years. What I like to do is have a user form that will update the payment amount and place an "X" in the month field. See the attached to see the layout of the data tab. I can make the form, but I don't know how to tie it the data tab to update correctly. It is a rough draft of a budget sheet I've been working on, so please bear with me on the format as it still needs work. Please let me know if what I am wanting to do is possible or if I need to totally redo my datasheet to make this work. I have a rough-looking form, but agian not command button placed yet.

Thanks for the help in advance.