The boss said he would give me a raise, but he didn't even mention it to me because my salary will be paid soon this month. How should I remind my boss of this?

The boss promised to give you a raise, which shows that in the eyes of the boss, you still contribute to the company and the boss still appreciates you. I suggest you inform your boss by SMS or email. Actually, it's nothing. You deserve it. Speak out boldly. Don't be shy. Everyone is selfish. To put it bluntly, we all work for money. On the contrary, if the boss thinks you are unworthy, he will be very polite if you don't resign.