Before he was an okay MMA fighter, Hidehiko Yoshida was an incredible judoka with a deadly uchi mata.
In the following video, he gives a few excellent tips on the uchi mata, such as not stepping in too close, almost pulling more up than back, and exaggerating the pull when doing uchikomi.
Of course, he makes it look easy, but it’s not easy. The reality of uchi mata is that it takes thousands of repetitions through uchikomi, randori, and a feel + timing to execute all the fundamentals of the technique in competition. I know where I’m supposed to step and how I’m supposed to pull, but doing it in a way where the opponent doesn’t see it coming a million miles away is the challenge and art of it.