If you want to be thorough it takes time. Alternatively.
1. Take it to the eastern Europeans at the supermarket car park. Cheapish and apparently not a bad job. Might take your car for a spin while you're choosing between high fibre breads because you've not been regular recently.
2. Take it to a drive through car wash, cheap and quick but you might find the car lacks windscreen wipers and has a burnished look at the other end.
3. The full monty as per the thread, but no clay bar and no polish just a quick wax seal to finish. Something like Autoglym Deep Shine is good for this. Slow and can be expensive if you buy all the good gear, this will give you huge satisfaction when you stand up and look the car over at the end of the session with a nice cup of tea. Of course it will have still taken all morning and you'll have a bad back for a week. Not for everyone.
4. The dad wash, grab the hose, some fairy liquid and a 20p sponge. combine to remove all dirt from the car, very quick and very cheap. Might not do the paint much good and will be unprotected.
I think that's everything.
For the interior, hoover and some dash polish with a microfibre cloth will work magic. If you want to get serious with shampoos and what not I'm sure someone will be able to guide you. I've only ever used the Autoglym interior shampoo thing and that was sufficient.