Maybe get booklet RC4070, "Information for Canadian Small Businesses", from the federal government of your choice.
You also need tax form T2125 and booklet T4002, as well as the regular T1 and all the other forms. T2125 lists the major categories for allowable expenses. It might be a good idea to use these same categories for your accounting. Spreadsheets are your friend.
Keep receipts for everything. If necessary, write on the back what the receipt is for.
Maybe have 12 envelopes, one for each month, and put receipts into appropriate envelope. Although, you may not have that many receipts. At the very worst, update your accounting at the end of each month. Don't wait until the end of the year.
Track all your car mileage (kilometrage ?) as well as business mileage. Either buy a mileage book for $4 or print your own. Keep all car expense receipts.
Track each major purchase, such as camera, lens, etc, so you can see how it's being depreciated over time. When it's sold, written off, etc., you will know exactly what it's worth.
It helps to separate your personal life from your business life as much as possible: separate bank accounts, separate credit cards, separate cameras, separate computers, etc. It's okay to use personal gear for business, but using business gear for personal use can cause issues with tax deductions. This is why you have to track car mileage - to figure out exact personal and business use (unless you happen to have two cars).
Using an accountant can be a good thing, but you should know the basics. Accountants know much more than just how to fill out a tax form.
It's difficult to give an accounting course in a forum post. There's probably some night courses for small business accounting.