I'd like to offer you a tipor two if I may,
I like to use steam cleaners/extractors because I think they don't leave as much residue in the carpet as the shampoo only machines. Just my experience. I like to pre-scrub heavy traffic areas like entryway or by back door,etc. Spots will be easier to remove also.I make up a little bucket or dish pan of warm water and some of the detergent that goes in the machine. Then I use a plastic bristle brush to work a little sudsy water into the stain, then blot it up by laying a dry terry towel on the area and pressing down picking up as much moisture as I can. Here's the thing. You don't want to drive the stain or any other dirt down into the padding.So don't get the carpet too wet! Another thing you can do even before you pre-scrub is spray the stain with a product called Folex Professional carpet spot remover. You spray and with a small clean terry towel just lightly work it in, it's clear, and blot up the stain. It's the best I've ever used, You can find it most every where even major super markets. This is my first step before anything else. Here is what I was taught from the pros, take your machine and run it over an area thats extra dirty with out the water spraying from the machine, just the soap from the machine if you can. Go ahead and run the scrub bristles on the machine but don't spray with steam or water , just let the machine scrub for a few seconds or a pass or two over the area then use the suction of the machine to pull up as much soil as you can , then go ahead and run the machine over area and use the steam or spray rinse and vacuum or extract as you normally would. Hope this isn't confusing. You just don't want to drive the stain or extra soil down into the padding. You don't have to do the whole room that way just extra dirty areas. Be sure to rinse the areas where you used extra effort cleaning so theres no residue. I was told that any remaining carpet cleaning solution left in carpet will attract soil faster! I'm sorry this ran so long but I hope it helps some. Get the Folex, you can use it on clothes and other things that need spot removing! Good luck. Other main point is if you think it's possible that a stained area may have some of the stain down in the padding, you really need to get that out or the stain will return!Billy