Gradually
Steps
adverb, noun
Step by step. If you take step by step, you're moving up gradually, taking steps.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
私の日本語が段々うまくなっていると言ってもらえて、すごく嬉しいです。
I’m glad to hear that my Japanese is gradually getting better.