Collinite, you can get online from clean your car
For washing NEVER use a sponge, get a woollen wash mitt.
If you have not done your car for a while, you will need to clean the paint. You can either use a detailing clay bar or sonus paintwork cleaner or Auto Glym Cleanser.
Once the paint is clean, polish it with Auto Glym Super Resin Polish. That will give the shine, then finish of with a 2-3 coats of Collinite
It will look mint after that.
Mer has been recommended above, yes it gives a good shine but its about as durable as a soggy piece of kitchen towel
If you are on a tight budget, Meguiers 1 2 3 is reasonable

You can get that from Halfrauds.