Control the Inside Arm
This will shut down most of the defense mechanics for your partner and allow you to have more control over the situation.
Keep Your Partner on the Ground
Not allowing your partner to turn into you is one of the most important points behind this submission.
Focus on the Shoulder
Having the elbow at 90 degrees or less will significantly raise your success when it comes to this position.
Always keep in mind Kimura position/submission is visible from many positions, top control, side control, guard, half guard, and others. Keep your eyes open and continue hunting.