Once you think of a number my first guess will be 50. If it’s higher, 75, and so on. It’s a common strategy which normally works. For example: if it’s lower than 50, then 25. If it’s lower than that, 12. If it’s higher than that, 18. If it’s lower than that, 16. If it’s higher than that, 17. If it’s correct, yay I win. I won’t repeat numbers or guess a higher number when I’m told lower or vice versa. I’ll also try to guess more commonly selected numbers when possible, such as even numbers.