The first thing to do when you are deciding how to deal with a stain is to work out what caused it. The principal thing to determine is whether it is an oily, or a non-oily stain. It’s important to figure this out because it influences what you’re first step will be.  The majority of chemical stain removers are designed to work on all kinds of stains. Finding out if it is an oily or non-oily stain is mainly to direct your immediate response. Tips for which home made stain removers work best for specific stains are highlighted in the third method. If the stain is oily, avoid the obvious temptation to rinse it under cold water straight away. Oil repels water, so any water than comes into contact with the stain could contribute to it setting more strongly. Instead, dab it with a dry paper towel. Oily stains have a variety of sources, but most commonly include:  Grease stains. Mascara. Lipstick. Foods which are rich in oil or butter. Once you have applied the stain remover, you simply put it into your washing machine and wash it as normal. Be sure to read the instructions carefully before you do this to check if the product you have recommends a particular temperature.

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Write a summary of the previous text in Chinese:
找出污渍产生的原因。 要是油性污渍，就不能用水洗。 放入洗衣机。