How to create an ongoing sales spreadsheet that also auto-generates monthly breakdowns?

[ConceivablyPerfect]

Hey, I'm not very good with Excel and I have to create an ongoing sales spreadsheet that lists sales by order of when they come in. This part is easy. The harder part is also generating, in additional spreadsheets, the same data but organized by month (ie, January, February, March, April, etc).

I've been racking my brain trying to figure this out! I would really appreciate it if someone could show me how to do this! I'm attaching a spreadsheet that I've been working on with the formatting. Thanks!!