*rinse in cold water and allow them to soak in cold water until you are ready to wash them.
You don't have to soak them but doing so will help reduce the chance of staining.
Your pads should be washed at 30 degrees without fabric conditioners. Using fabric conditioners can leave a fatty residue on the fabrics and this reduces the absorbency of the pads. Always air dry your pads; line drying in the sun is best to reduce stains or on an airer in the house is just fine.