Hello, thank you for your question.
If the dispositions of your securities result in capital gains you can reach out to the institution of which you are trading with and request a realized gains/losses statement for the calendar year. Instead of detailing each and every disposition in Schedule 3, based on the aforementioned statement you can input the net capital gain/loss in one entry.
However, I need to remind you that day trading can be considered by the CRA to be business income. There are a number of factors that must be taken into consideration to determine if this income is business income or capital gains/losses. I would advise reviewing this link for further information.
