I am running an electronic repair shop right now. It is a sole proprietorship as of right now. When I do my income taxes, what documents am I going to need to do them for the business?

Also this is a little off topic but what financial documents should I be doing? Documents like a balance sheet and others? Or how does that work or is best practice?

Please Help.
Thanks !
I didn't find the right solution from the internet.

References:
- http://www.small-business-forum.net/accounting-and-taxes/18432-income-tax-help.html
- Installation Video Examples