A friend of mine use to detail cars for a living and still does from time to time. Here is an email he sent me when I asked him for advice on products for my BMW......
"I don't have any experience with BMW products. You may want to google search. There are only several companies making car care products, so much of it is rebranded. I'll try to focus on what I know below.
For washing, I like to use microfiber or lambswool wash mitts. You can also find sponges wrapped in either of these materials. In terms of detergent, any of the Meguiars more expensive ones are fine (NXT, Gold Class, Ultimate). Duragloss, sold at Carquest, makes a very good detergent. Try to wash from the cleanest parts of the car to the dirtiest. I actually keep a separate wash mitt for the lower (dirty) parts of the car. I usually go 1) hood, roof, trunklid 2) glass 3) fenders, upper half of doors 4) lower half of doors, bumpers 5) rocker panels. For drying, I use microfiber towels. I really like waffle weave microfibers for drying (
http://www.autogeek.net/cobra-guzzler-hd-towel.html). I actually bought a large microfiber meant for drying from Target or Walmart once and it was of good quality. I do not recommend chamois (natural or synthetic). I have a suspicion that dirt can get stuck between the chamois and the paint and cause micro-scratches. Also, there isn't any good way that know of to clean chamois (with microfiber, just launder like any other towel). I usually follow every wash up with spray wax. I actually only use traditional wax on my car every few months.
For wheel care, you can buy wheel cleaner from any auto parts store (store brands are fine). If they aren't too dirty, you can actually use a wash mitt you dedicate for wheel cleaning and the same detergent and water you use to clean your paint. This is actually my preferred method, but I do have to use wheel cleaner when the brake dust is really bad (usually in spring). A wheel brush like the one in that kit is great. Also, a flat scrub brush (like one you would clean a spot on carpeting), is good for quickly scrubbing the sidewalls of tires. In terms of tire gloss, I really don't like shiny tires, but I do like black tires. I try to stick with anything in stores that says "matte" or "natural". I haven't tired
http://www.meguiarsdirect.com/produc...p?T1=MEG+G4116 but I've been meaning to. I usually just spray on the tire and then wipe with a sponge that I keep around for that purpose. The best product I've used for tires and interior plastics is called 303 Aerospace Protectant, but it's really expensive.
In terms of waxing and polishing... I've had good luck with an inconspicuous product called Collinite Insulator Wax (
http://www.autogeek.net/collinite-in...r-wax-845.html). You can find it locally at some Advance Autos and perhaps Carquest. Another good product (and actually, a pretty good lineup), is Duragloss (
http://www.duragloss.com/catalog.asp?catid=89) sold at Carquest. The benefit of Duragloss over Collinite is it is available as an all-in-one product. It is not as durable as Collinite, but it is more convenient. In fact, I've actually used Duragloss 101 and then Collinite before winter with good results. I'm not particularly sure of the differences in the lineup, but it looks like people online really prefer 105 and 101 to 111. I think I'd go for 105 (total performance polish) if I were buying again. On this note, for spray waxes, Duragloss Aquawax is excellent as well as Mothers Synwax Spraywax. Meguiars also sells spraywaxes that are good. You only need a spritz per panel, wipe with a clean microfiber. One bottle should last you a long time.
For waxing technique: I apply a spritz of spray wax to a foam applicator (
http://www.amazon.com/Pinnacle-Natur.../dp/B0002SPBZ4, you can buy these in any local store) just to get it wet. Then I put a dab of wax or polish on the applicator. I go in the same order as washing. I do linear motions in the same direction as air would flow over the panel at spped (whoa I'm pretty crazy). It's really difficult to explain this online, so if you need help perhaps we can have a demo day. I let the wax get a haze, then buff off. I do not apply wax to the entire car and then buff off. I usually do half the hood, then the adjacent fender, then buff off the hood. Waiting too long means a lot more effort buffing. It isn't detrimental to the paint. I should note that all of these products will not damage the paint. I buy microfiber towels at Target or Walmart (or an auto parts store). They usually pretty small (less than 2 ft x 2ft). You need 2 or 3 to buff off an entire car. It's a good idea to keep a surplus of these around. They excellent for a lot of tasks, and safe for paint. I wouldn't use a polyester towel on paint.
I have very little experience with leather, but this may be where you want to invest the money you have to use at the BMW Accessories store. Just follow the directions. Also, keep the dash well protected (Meguiars No shine should be good, or the BMW brand).
There are more..errr... invasive paint care procedures(i.e. clay bar to get the paint very smooth, polishing to remove imperfections like swirl marks), but I think I should really show you how to use these in person. They shouldn't be done more than once a year (maybe twice a year for clay barring). If you wash and wax properly polishing will be required less often."