This is how I clean my leather seat
(do this once a month)
Clean and conditioning are the keep factor is keep the leather seat last a lifetime (not to mention a special (luxurious) unique leather small in the car)
List of parts: (you can get these at your local auto part store)
Lexol Leather conditioner
Lexol Leather cleaner
a small bowl (you need this)
Step1: put a little bit of water in the bowl, heat it up with a microware (30sec) to get hot water
Spray some Lexol Leather cleaner into the bowl and mix it up. You should see a lot of bubble (soap like)
Notes: Spraying the cleaner on a damp cloth as described in the Lexol's cleaning instruction does not work as well. The warm soap solution in the bowl works a lot better.
Step2: Wet the terry cloth, and start wiping the leather. Small section at a time. Make sure you wipe the towel following the pattern of the leather (all directions). (don't use too much water/soap solution, just wet enough to clean, we don't want to see running water here)
Keep a dry cloth with you to wipe the excess soap and dirt right after you clean each section.
Sorry about the picture, it's a little dark, my seat look pretty clean until I clean it (BTW, no one is seating here, and it still collect dirt)
Repeat the same process for all the seats AND the steering wheel, it's leather also.
Leave the car with the windows open for about 10 min. (make sure leather is dry)
You are ready to apply the conditioner. Just put the conditioner on the clean terry cloth and apply on the leather seat (make sure you cover the whole surface with conditioner)
Leave it seats for 10 min.
Step 4: use another clean terry cloth to wipe all the seat to make sure no excess conditioner is on the surface.
Make sure to do this step, in contrary to the popular belief, (of leave the conditioner there), the excess conditioner on the surface of the leather will ATTRACTS more dirt, make sure you clean it.