Google the 2 bucket method. Essentialy one bucket of expensive car shampoo, another full of either water or some cheep crap just to disolve the gunk off the mit.
Use those microfibre noodle mits, Much less damageing to paintwork than sponges.
Always best to ‘clay’ the surface before polishing, it’s not as daunting as it sounds, just always make sure theres is lots of liquid polish on the paint and dont bother below the doorline, or at least if you do use a small bit of clay and bin it regulalry.
Use a half deacent polish to remove fine marks all over once a year.
Seal the paintwork after polishing, think of it as polishing blunts the edges of scratches, sealing fills them in.
Then apply as much wax as you have time for, 3-4 coats isn’t a bad idea as clay+polish will strip off any that was there. Then apply 2 fresh coats each time you wash. The more expensive the shampoo the less wax it will strip off, meguires gold is about £30 a bottle but leaves a much nicer finish than £5 wash’n’wax.
Trigger spray tyre blackers work better than aerosol ones IMO, and easier to apply to a cloth to wipe down interior pannels, making them black rather than shiny.
Glass cutter + polish on all the windows and lights (unless they’re plastic).