ALWAYS blot up a spillage using white absorbent paper (such as a kitchen towel). Using a white paper means that you can easily see if the paper is picking up anymore. When no more liquid is being picked up, even when pressure is applied, you know you have got it all.

Before treating a stain in the carpet, test whatever treatment you plan to use on part of the carpet which is out of sight. That way you can check to see if the treatment will have any negative effect on the carpet. Use a dabbing motion to remove a stain, and work from the outside inwards to prevent it from spreading.