There are a couple of aspects to small business accounting and record keeping- the actual structure as well as accounting software.  Structurally, you want to separate your personal self (and expenses) from the business as much as possible.  That means setting up a separate business account, not running illegitimate personal expenses through the business.  Just because it is via the business bank account doesn't make it a business expense.

I would recommend tracking income and expenses via some sort of software, whether internally or via an external bookkeeper.  In my professional opinion, none of them are as off the shelf as the software companies would make them out to be- I've seen a lot of messy files – "I entered everything in Quickbooks".   Note that Quickbooks online does not have the full blown functionality of Quickbooks desktop.  There is also some up-and-coming cloud based software, such as Xero, Freshbooks, and that are worth a look.