Prepare the sneakers
The point of the Vaseline is to protect the sole of the shoes so that the dye will just color the fabric. Rub a good amount of Vaseline all over the sole and edge of the soles to ensure that the dye will only go where you want it to go.
Dip the sneakers into the dye
Prepare the dye according to the directions on the package. Hold the sneakers by the heel and dip them into the dye solution. If you want the ombre effect to start a different part of the sneakers, you can dip that part into the dye instead. Use your imagination!
Spread the dye
Take a towel or sponge and spread the dye from the front of the sneakers towards the back (or towards wherever you want the dye to spread).
Let the sneakers dry
Hang the sneakers up to dry. Hang them up so that the lightest part of the sneakers is up and the darkest part is down. After the sneakers have dried, you can rock your unique sneakers or you can dye them more with a different color.