Pet stain removal depends on a few common sense factors. Understand that older stains demand lots of effort. Fresh stains, by definition, are totally curable. Stop torturing yourself if you consider your pet stain situation is incorrigible. Maybe you won't have success in totally removing the pet stain. But you can always improve its condition. Let's start with the basics. When applying a detergent go from the outside to the inside. Avoid making the common mistake of scrubbing circularly from inside to outside. Do this and you'll save yourself another big headache.
Don't despair no matter how scary and big the pet stain seems. Use the force of nature in your advantage. Think about how temperature manipulates the physical realm. When something gets hot it melts, making it easier to move around and eliminate. Methodically heat up the pet stain in careful fashion. Just don't burn the whole carpet. An industrial incinerator is not the ideal tool for this job. Start with towels soaked with hot water. Apply the towels on top of the stain. The pet stain should transfer from the carpet to the towels. Repeat several times.
When you finish cleaning, never forget to quickly dry the affected area. A high powered fan can take care of the details. Have one handy during the pet stain removal process. When you finish you might notice that remaining solids stiffen up. Treat these a bit differently. Smash the remaining solids apart and after pick up the pieces. If appropriate, use a vacuum to suck up these little crumbs. When finished, rinse the affected area with water. A little soap never hurts. Finally, let your carpet rest for a few days. It should then look as good as new.