It is very important for you to keep track of the company performance in each period , so that you can maintain and upkeep your business .
After you have done the transactions with customers and made some expenses for your company, you have to keep all theses records ,including monthly bank statements,every contracts,invoices and receipts about the company.
After that, please keep them in the safety place for book-keeping by your accountants (Shoe box is a nice place for you to keep them !) .
Finally, your accountants will help you to do the management accounts and prepare a year-end financial statement for you.