I always work inside out:
1. remove all the stuff in the car, take out the mats etc
2. for the inside, crack out the dyson and vac the whole car through - under the back seats, parcel shelf, boot, under the font seats. Basically remove all traces of anything that the vac can get hold of
3. been using turtle wax interior cleaner. spray on, leave 30secs then buff off with microfibre cloths
4. Clean the seats with upholstery cleaner (if they need). Stuff from halfrauds is so so. Need plenty of clean water to rinse off the cloths. Might have the upholstery cleaned properly sometime soon
5. Glass clean all inside windows
6. Vac all the mats off and put back inside
Outside:
1. Blast any crap off with the hose, get car nice and wet
2. Car shampoo, couple of buckets full, sponge and wash mit. Give it a good going over, make sure I clean all the insides of the doors etc
3. Spray it all off, shami it down. I often then move the car which helps move a lot of water in little crevices and keep drying it to remove all the water
4. wash it (Mer wax). Applicator to put it on and then micrfibre buff it off
5. Alloy cleaner (not acid variety). Clean all the alloys, then wash them off with water
6. Turtle wax tyre dressing, spray all the tyres down with this
7. Do all the trim last, to be honest think back to black is crap and am going to try the Kiwi polish method
After that, wait for it to rain and ruin all my handywork