I'm still learning, but for me what has helped out is:
1.) Going a little faster
2.) Practicing on grass or wet blacktop
3.) Really throwing your weight forward. Think "balls on the stem."
4.) Pushing down on the back foot and simultaneously pulling up on the front foot.
5.) And most importantly: Commitment! Don't get timid about it, just commit to the skid and lock up.
For comparison, I'm running 48/17. Considerably easier than your 48/15.