How to wash an oriental carpet yourself
Step 1 The scene of the crime
Choose a flat area such as a concrete driveway, wooden deck, or pool surround. A gently sloping driveway is a good choice. Make sure it is clean and large enough, has a nearby environmentally safe drain (some municipalities will not let you put suds into the drain) and a plentiful supply of water. Watch the weather and choose a time when you have a few fine warm and even windy days ahead. There is usually only one or two seasons suitable in most climatic zones, and they around spring/summer.
Step 2 Tools
Water, Water, there is never enough water! Have at least 2 garden hoses on hand and more if your victim is roomsize.
Brushes - two, a nail brush for small areas and fringes and a soft brickies brush. Hard brushes are out! Better to use a straw handbroom or bare hands.
A squeegee. Not the window cleaners' rubber type. You may have to make your own from a piece of pine about a foot or 30cms long and big enough to hold. Something around 3x1inch or75x25mm. Sand off one horizontal edge to pencil roundness.
A bucket for mixing suds and a cup and small artists brush for applying neat soap.
Soap. This is not really as important as people think, and one can be too neurotic about it. This instruction covers 99% of household rugs. The fragile and ancient museum antiques should be given to a specialist to wash. You may use the non-stearates Sodium Laurel Sulfate, Sodium Dodecyl Sulphate, or mild clothes washing soaps like LUX flakes, or Sunlight pure soap. The wool wash section of the supermarket will have a range of "specially for woollies" soaps and these are probably the best and easiest to use in most cases. These wool washes will not clean cotton warps/fringes so use the pure soaps on the cotton. The important thing is to have a reasonably strong suds solution in a bucket. You will apply this to the wet rug. Never apply neat soap to a rug except in small controlled stain areas. Never use bleaches or strong soaking soaps or harsh detergents, or water softeners, as they will ruin the handle and dry out the lanolin.
Step 3 The Victim
What sort of rug is it? Is it heavy, light, old, new, damaged, stained etc.You should not attempt a badly stained rug nor should you wash a valuable antique rug yourself. You should not wash a carpet too big or heavy for you to turn over when wet. 3x2metres or 6x9ft is usually the householder's maximum.
Step 4 Preparation
Running dyes are your biggest problem. Certain types of rug are out. Such as Nain, Turkmen(istan), much Iranian and Turkish village products as well as Afghan mowri etc. The list is endless. The colours that run can be deceptive, also. ie. Blue is nearly always a safe colour but it is a running colour in 1960's and 70's Ardebils, even though other Azerbaijan rugs of the period all have good blues! Generally the more synthetic or hard/saturated a colour looks the more likely it is to run. ie. Most bright oranges run as do a lot of dark maroons. There are some tricky strange greens. The older a carpet the less likely it is to run with good old 100% vegetable dyed rugs totally safe.
To check for running colour take a white absorbent cloth like a nappy or multiple white paper towels. Wet a small area of the rug. Only wet the pile or nap, do not thoroughly soak. Choose an area that has all the colours. You may have to do two areas on some rugs to ensure all colours are checked. The size of the area will depend on the fineness of weave and the intricacy of design but the size of the palm of your hand is usually sufficient. Place the dry cloth on the wet area and apply pressure and hold for a few minutes (or apply a heavy weight). If there is running colour your white cloth will be stained. You may even have the design imprinted into the cloth! NOTE: this method is not completely foolproof as some colours will run only when soaked for hours as in washing! However, those colours are unusual and the running is usually slight/insignificant.
The Zen of running colour. A rose is a rose is a rose. My personal belief is that if a rug has running colour then it should be washed (quickly and carefully) and the colours be allowed to run (as little as possible). A running dyed rug is a running dyed rug. The dye is intrinsic to the climate, the people, the oeuvre, and is part of the paradigm that is the rug, I mean, why worry? I believe a dealer is dishonest/ignorant/incompetent if he/she sells an unwashed running dyed rug. It can be a time bomb to the owner who is to become emotionally attached to it! Some old synthetically dyed Luri rugs look even better as "mud and blood" and some Turkish tourist rug shops equate "mud and blood" with antique value and wash to achieve that end.
Pre-wash cleaning. Preferably you will have had the rug upside down in it's normal place in the home for a few weeks to gently loosen the base fibres, releasing deep grit. If you have just bought the rug it may be carrying moth or disease mites so start here. In the open, beat the rug upside down. Turn it over and vacuum. Repeat till dust and especially grit more or less ends. You may hang it on a line to do this if the rug is strong and you are careful. Do not vacuum your valuable antique rug, brush with a straw broom instead.
Step 5 The Wash
Firstly fill the rug with water. This will take longer than you think. Lift up the sides to ensure the back is wet enough to verify you have completed this step. You may roll the rug up and unroll it to help the absorption of water.
Secondly lightly squeegee the excess water from the pile/nap, being careful to only stroke in the direction of the pile/nap.
Now is the time to apply the soap solution. Using the soft brush or your bare or rubber gloved hands massage the suds into the pile in a circular motion. Walk over the rug like you're treading grapes for wine. Now squeegee again and your white suds should be a shade of cafe au lait.
Step 6 The Rinse
This is possibly the most important step. Fill again with water and squeegee again. Repeat and repeat until there is only pure clean water coming out. You may wish to turn the rug a half at a time and tread grapes from the back to help release the grime. It all depends on the thickness and how dirty the rug is.
You may have to resoap and repeat the wash process again. As one of my teachers, a certain Mr. Beztchi in Iranian Azerbaijan would tell his workers, "don't stop until you can drink the rinse water".
Step 7 Drying
Following the final rinse you should repeatedly squeegee out as much water as posible. Leave to dry for an hour or two in the sun. Find some grass or lawn and turn the rug over and complete the drying upside down. The lawn is very important as it stops the build-up of static electricity, destroying the sensitive lanolin molecules inside the wool fibres. You may turn back to dry the pile/nap for a while and complete the drying upside down if the rug is thick. A thin rug will dry in a day and a thick rug may take two with even further drying on a third.