A couple of suggestions.
1-Timing:
If you have a 5 step approach, try to push the ball at the same time as your second step begins.
If you take 4 steps to the line, push the ball and walk at the same exact time (this is a good way to correct early/late timing, which without having the benefit of knowing what you look like while executing a bowling shot, is impossible to say what your discrepancy might be).
2- Focus and cadence
Keep your eyes on your target as you approach the line, and make sure your steps are not too fast nor too slow and are always repeated the same once you have a good "feel"--and as you are nearing the foul line, get low with your legs (do not overlean with your upper body).
3- Delivery
As your slide foot hits the line, keep your eyes fixed on your target (this cannot be emphasized enough), make sure your sliding knee is bent AND balanced, and follow through with the hand AT/TOWARD your target FLAT with the lane (chase the ball with the hand), all the while WATCHING the ball cross your intended path, while saying BALANCED (not getting up) until the ball is near the pins.
There are so many nuances to the game of bowling, but the above 3 cues are all vital to a sound fundamental game, regardless of one's style.
Good luck.
"What is life? It is the flash of a firefly in the night. It is the breath of a buffalo in the wintertime. It is the little shadow that runs across the grass and loses itself in the sunset."
—Chief Isapwo Muksika Crowfoot's last whisper