MODS PLEASE STICKY, so I do not have to keep repeating myself.
Disclaimer: If you do not have all (key word "all") the tools and products to do a proper wash then I highly suggest you go to a proper detailer who does. Always wash car in a shaded area. Always use filtered and softened water.
Here I will explain how to properly wash and dry your vehicle and I will go over both the dual bucket and foam gun methods.
Dual Bucket Method
Tools you need:
-2 buckets not 1 but 2
-top seal for the buckets as well but not needed
-Wash sponge/mitt the only types you should use are: natural sea sponges- The natural fibers will not scratch the paint. They will actually pull contamination from the paint and into its pores and compartments. If it is a new sea sponge always rinse before use to make sure any shell debris is out of the sponge. Sheepskin wool mitt- It is extremely soft and the nap is very deep for contamination housing. However, downside is it won't last as long due to it being natural. Last we have the microfiber mitt (my personal favorite)- A combination of polyester and polymide make this option very good at being able to scrub contaminants off without scratching or swirling the paint. It will also have a very long shelf life as well as be very effective in trapping and housing contaminants into the mitt. http://www.autogeek.net/sponwasmit.html
-The proper car shampoo. If you have a layer of wax you intend to keep then you must get a wax friendly car shampoo. Otherwise the shampoo will strip the wax. Most of you diyers make this mistake of waxing your car and then the next week use the car shampoo you got at Auto Zone or Walmart which are all usually not wax friendly unless it says it is. Again make sure you are using the right car shampoo.
-Water softening system
-Pressure washer(helpful but not needed) I would stick to a electric washer just because they aren't too strong and you will have less chance to chip the paint.
-Microfiber towels(formulated for drying) we in the detail world call them guzzlers.
-Microfiber towels(formulated for glass) usually a waffle style weave.
-Metro Vac used for blowing any excess water out from trimming and molding or head/tail lights.
-Quick detail spray used for touch ups and door jams. This is probably one of the few things you can get OTC. Meguiars NXT or Gold Class are good solutions. Of course there are products better like Pinnacle, Blackfire, Swissvax, but for you guys those will do just fine. I myself use Meguiars detail spray.
Wash Process:
Your wash technique is only as good as your prepping as well. Keeping a clean work environment as well as a organized one will make a world of difference. I have been doing this for almost 18yrs now I think I know a thing or 2. Making sure your microfiber products are always kept in a sealed environment either in a container, box, glass cabinet, even a plastic bag works. But make sure they are not sitting out in the open. Things in the air can settle on them or particles could be swept up and then settle on them as well. This means when you go to wipe the car you are applying all that onto the car. Also keep your wash sponges safe as well. I utilize a glass display cabinet to house all of my microfiber products. Someone mentioned they like Chemical Guys. They make a great product, however, at one of their shops called "Detail Garage" they are a very well known shop and have done "how to" vids on youtube. One of the first things I personally noticed that I would change is that they have all of their microfiber products, sponges, applicator pads, polishing pads all out in the open. If I were to do a consult with them I would recommend they change that and keep them out of the elements. Also proper wash attire gets overlooked. Again I know I sound like i am picking on Chemical Guys, but in another one of their vids they showed a gentlemen who was wearing a belt with what looked like a metal buckle. Again take that possible scratch out of the equation. Always wear car friendly attire when you are doing car care. So stay away from belts, jeans, pants with buttons, jewelry is a big one, take that wedding ring off, necklace, bracelet, and for my kneepad team you gotta get rid of the tongue/lip rings. Never cross contaminate! What that means is if you used a wash mitt to do your engine bay or wheels do not use that same mitt to do the body of the car. Always separate tools for each use. Also not needed but encouraged is to wear some sort of protective glasses.
First start by getting your dual buckets setup. Place them enough distance from the car and you so that you are not going to hit the car with them but close enough you can dip and apply. Depending on the severity of the wash will depend how much shampoo you use. Usually it is very concentrated stuff so you do not need a lot. I would say a few cap fulls and you are good for a 5 gal bucket. Again the amount will vary depending on size of vehicle, severity of application, and the type of shampoo. The key here is soap suds!!!!!!! So that means make as much suds as possible! If you need to put more shampoo in to make more then do it! Start by pouring the product into the bucket and then spray into the bucket making suds. Those suds what they will do is chemically bond to the contaminant and it will create surface tension to where the contaminant will automatically rise to the top of the surface of any suds/water that is on the car. This means when you go to wipe the car you will not get contaminant to paint exposure. After you are done creating the suds. The other bucket is for rinse only. So just fill it with water. Again both buckets should have a grit guard in them!
After you are done setting up your buckets, you will then rinse the car. This means go over the entire car and hose it down liberally. While you are doing that the suds may have decreased in the bucket. Thats ok just apply more water and you should get more.
Prime your wash mitt. Do this by soaking the mitt then applying it in the soap suds and make sure it has a to of suds on it.
Now that you are ready to wash, if you plan on doing the wheels, tires, engine bay I recommend you do those first before washing the car because any overspray of water or chemicals you can clean during the car wash phase. Start by doing the top first and work in sections. I would not do anymore than 3-4sq ft sections. Just wipe back and forth and do NOT press into the paint!!! This is how most people cause scratches and marring. Just wipe softly back and forth. I apply just enough pressure to make sure I am in control of the wash mitt. After you are done with each section you place the mitt in the rinse bucket. Shake to dislodge particles and contaminants. Then i would do one more step and that is to take the hose and spray the mitt off. Then dip it into the suds bucket. And keep repeating those steps. Work your way from top to bottom. Once you are done washing, you do another rinse. This is the rinse down phase.
Once rinsing is complete now is time to dry the car off. Now you can use one of those jelly California blades however you need to learn how to properly use one of those and there is only 1 style of blade that works properly. So if you do not know what you are doing then stick to using the guzzler microfiber towels. I would probably use 2 of the 16x24 towels. Now when you dry the car, it helps to fold the towel in at least half but usually 4 folds is better. This way the pressure applied is more evenly distributed. Again stay away from rubbing too hard/ You should not have to rub hard. Now if there is a spot that requires rubbing that is fine but only that spot. It will later be corrected during the correction or the extraction process.
After you are done drying the car, I would then take my Metro blo/vac and blow all the excess water from all the little crevices of the car. Then I detail all door jams, trunk, and hood jams as well. This will conclude the wash process.
Foam gun method
tools needed:-everything mentioned previously except you do not need your buckets w/ grit guards.
-And of course the foam gun. Now there are 2 different styles of guns. You have a water injected foamer and a air injected foamer. The water foam gun you can literally attach it to a normal garden water hose and use it that way; others get adapters to use it with a pressure washer. The air gun you need a compressor. I would recommend a compressor that can produce 5cfm at 90psi. Both guns work amazing for soap suds and washing the car. Either one you can't go wrong. I personally prefer the foam gun method any day over the bucket method. The amount of soap suds you get from a foam gun is just amazing! This will ensure you keep your paint protected during the wash process.
As for the wash process it is the same like the dual bucket except you use the foam gun to sud the car instead of the buckets. I would also sud the entire car first and let the shampoo work its magic while you do each section. After each section spray the sponge with more suds and go to work.
I always recommend once you are done, to properly wash your microfiber products and then put them back in a safe location. Clean up your environment and get ready for the paint extraction and correction processes.