To create particles, go to the particle sprite. For the purpose, put 1 for particles that fling around. For 2, go to the part of the custom block that says Y change for 2 and put a positive value to make it go up and a negative value to make it go down. For 3, it just stays in one spot and grows bigger and fades out. Put in the X and Y coords for the particel to spawn in the areas marked X and Y. The wait time is how long it takes to create another clone. The placement is how front or back layer it is. The costume is where you put the costume number of the particle.