when i started doing gymnastics after years off, i also had to relearn my steps on vault. what helped me was:
1. figure out which foot you want to hurdle to the board with.
2. have someone stand near the end of the vault runway to watch where either your left or right foot lands. for me it was the same foot that i hurdle with.
3. standing on the spring board, all the way to the end with the springs. hurdle off it and run as fast as you can, all the way to the end. don't think, just run, someone else is watching for you.
4. take a small step back from where they marked.
If you have a "danger zone" or the area just before the board that you don't want to run in--stand where that starts. Then, run about 10-12 steps and start where your last step hits (have a teammate watch where your last step hits).
Many people like to run the entire length of the runway, but I've learned that this is not the best thing to do. Many people believe that you need to run the full length to go fast, but in reality--the shorter the length the faster you run (this is why sprinters don't run marathons). Long story short--try not to take more than 13 steps and remember to speed up as you go down the runway.
I started a new vault and my steps were all wrong too until I had my coach but a block where I was supposed to hurdle so when I ran I had to hurdle over it onto the springboard I did that for a few practices and now I have me footing back.