Just get as many people to play your game as possible, and start play testing early. Play test as soon as you have the main mechanics.
Viewing post in Odd question about play session and difficulty
Appreciate the answer. I guess I should have made sure I prepare the right question to people whenever they playtest for me :0
I'll do some research on my side on discords servers for game dev, it might simplify the process of asking strangers to try my game (or reduce the shame of doing so ʕノ)ᴥ(ヾʔ )