"I will make an effort to change myself" 或 "I will work hard to change myself" 可以用来表示这个意思。
这个短语来自英语中"make an effort" 和 "work hard" 的结合，"make an effort" 意思是"努力"，"work hard" 意思是"努力工作"。
例句：
I will make an effort to change myself for the better. (我会努力改变自己变得更好。)
I know I have to work hard to change myself. (我知道我必须努力改变自己。)