If the thought of a large excel type spreadsheet seems overwhelming go back to the way we used to have to do things before we had computers. Paper and pen. Take a wad of lined paper and put the catagory at the top of the page. Then go through your receipts and put the items on the correct pages - date (even just month is fine) item, cost - note if you are taking items off say a walmart bill put the item down and then a plus t to mean add taxes to the total later. If the bill is specific like you bought one item on the bill and the taxes are done then record the total as is. Add up the pages at the bottom and then that gives you the totals to work with.
Star with household expenses as that is the easiest. Make pages for heat, hydro, water/sewer, property taxes, the amount of interest paid in your mortgage payments (bank will send you an annual statement usually).
Catagories I think I use are administration - I put things like my membership to CCPRN here.
Advertising if you paid for an ad, bought business cards, bought posterboard to make posters, etc.
Office - computer ink, paper for printing, pens, pencils, lined paper, staples, tape, paperclips, reciept books, binders, page protectors, whatever you buy to help you run your business.
Supplies - toys, crafts, food, cleaning supplies.
Repairs and maintenance - can be things like new batteries for toys, repainting the playroom, shampooing the carpet, replacing something damaged by a daycare child such as pushing the screen out of the door or yanking on a cupboard and breakng the child lock.
CCA which is if you bought big stuff and you just follow the chart in the tax package to figure out what you can claim ie transfer the total from the chart over to the other line.
Vehicle costs if you claim this
Forgetting now what else is on there but that is the basics, Yes it seems overwhelming but once you get started it actually goes not too badly. Start by dividing your receipts by month and then dealing with each pile at a time putting the totals from the bills on the right pages. Groceries can just go into a general pile as there are other ways to figure out the amount to use and there is really no consenses on this one.