Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: how do you clean the outside?
Document: When I opened  my box and took it out I was in ahhhh it is so beautiful. I'm a tea drinker I use it daily, it boils water fast and it feels sleek and clean. I love it and I'm sure its going to be my tea kettle for a many many years.
I thought it is insane to pay this much for a darn kettle.. but I realized I'd use this every day (I am Japanese, meaning I drink ton of green tea every day) and can't go wrong with Japanese product so I went and glad I did. This is clean and easy to clean and looks fantastic. Boilds water very quickly at full capacity and the handle doesn't get hot or doesn't feel flimsy. This is a good kettle that will last me a long time.
love everything about this kettle. very high quality and heats quickly. looks and feels like it will last a lifetime.
bought this for my fiance and she loves it. great finish and feel and cleans easily. no problems with rust or construction after several months. big plus that it's gorgeous even when not in use.
Well, perfect for me anyway. This kettle is beautifully designed and crafted from heavy gauge stainless steel with the only visible seam at the spout attachment. The top knob and handle are made from a slightly textured material that is both comfortable and aesthetically pleasing. Additionally, the spout pours a very controlled stream while the kettle remains perfectly balanced in the hand. The wide flat bottom insures a rapid boil and, in place of a screeching whistle, the lid dances discretely on the rim alerting you when it's job is done.
Well worth the money. A high quality piece that looks great and has excellent craftsmanship. Far exceeded expectations, pictures do not do it justice. Made in Japan. Will last 30 years unlike other kettles that end up in the trash in a year or so.Things that make it special-looks great on the stove. Wife was impressed.-Mirror finish is much better looking than picture.-Very high quality thin and real stainless steel.
We looked everywhere for the perfect kettle. This is it. A masterpiece of design -- they ought to display at the MOMA.
We bought this kettle several months ago when it cost $125, though we hesitated due to the price. It was worth every penny, maybe more. It's elegant and efficient, boils much faster than our old one, so smaller size (about 2 quarts or abit more) isn't a problem. It is a pleasure to own. I wouldn't order it in the brushed finish, however, as I think it would be too hard to keep grease- and fingerprint-free. Great product!
Water boils in 7 minutes for me.-Lid has 5 inch diameter which makes for easy cleaning-With handle folded down (awesome feature) and lid removed it is 3.5 inches tall for easy storageOthers reviewers mentioned the lid leaking when pouring. Lid is a good fit and rests with gravity.
This took weeks to get here, I presume from Japan. I have always had a water kettle and this time I wanted one with a seamless bottom. I got the mirror finish, and it goes nicely with the other stainless steel things I have. The Sori Yanagi kettle is both simple and supremely elegant. I figured the Japanese would know how to make a tea kettle, and we needed one bigger(and less expensive) than the classic ones they make. I am loving it. It heats fast.
Answer: Warm to hot water and dish soap - mildly abrasive sponge.