The cashier figures are only a technical frame. A minimum of C$10–20 and a maximum that often sits around C$3,000 per transfer come from the bank and the casino, not from what you can afford, and both change from one operator to the next. Read the exact Gigadat casino deposit limits in the cashier of the site you chose instead of assuming these figures apply. Then set a personal daily, weekly and monthly cap in your casino account, well below the bank ceiling.
Spins are a more honest measure than dollars alone. A C$100 session at C$0.50 a spin gives you 200 spins, and at C$1 it gives you 100. If you count a session that way, you see how short it can be before you send the money. A Gigadat deposit is credited anywhere from instantly to 30 minutes, so there is no waiting period in which you might change your mind. A limit you set in advance has to do the job that a delay would otherwise do.
Fees look minor. The service charges about C$1 or less, casinos often charge 0%, and your bank may add its own fee. Five small top-ups made while chasing losses still mean five fees and five decisions you never planned, and that is how a modest session grows without anyone noticing.