Dirt and grease would have accumulated of the leather seats since the last time you cleaned them. So, to start with, remove this dirt and grease. In order to do that, preferably buy a seat cleaner from your local store, or you may use a two-to-one mixture of water and general household cleaner. Gently rub the seats with a cloth or soft brush dipped in the cleaner until all the grease and dirt is gone from the seats.
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Now, using a damp piece of cloth, wipe off any cleaner residue that might have been left on the seats. After thoroughly wiping the seats with a wet cloth and making sure there is no residue left, you have to dry the seats. You piece of dry cloth. Make sure that the seats have dried properly because you do want the upholstery conditioner to loose its shine quickly.
Buy a good quality upholstery conditioner from the local store. Using a kitchen sponge, apply the conditioner all over the seats. Rubbing the conditioner into the leather is very important. Make sure you gently rub all the conditioner into the leather and leave none exposed because the more you rub in the conditioner, the longer it will keep the leather seats protected and shiny.
You need to keep the car shaded from ultra violet radiations to give the conditioner a chance to set in properly. Parking the car in your garage or in shade for a day or so would suffice. Before you start driving it again, gently wipe the seats one more time using a piece of cloth.
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