Washing is fine but it wont lift tree sap, bugs and general road grime that stick to your paint, making it rough. Idealy you want a good shampoo, wash mitt, at least two buckets, a good clay bar with a detailer spray, this will quickly and safely restore a smooth finish to the paint.
I use the Chemical Guys Extreme Bodywash and Wax shampoo and the Chemical Guys Extreme Slick Synthetic anti static polymer detailer with the large professional clay bar from car wash n wax.
-Static)
After the paint has been clayed you should polish the paint to get a good gloss, after polishing a sealant will seal in the gloss that the polish has given. The two polishes i use are Auto Glym Super Resin and Chemical Guys Pro Polish. The AG is slightly easier to work with than the Pro polish but gives just about the same results.
Waxing is the next stage, i personally stick with a pure carnuba, my personal choices are Chemical Guys XXX Hardcore Paste Wax, and Meguiar's #16 mirror glaze...nattys blue is also very good and will work well with the blue paint on your cup.
Places to buy from:
http://www.carwashnwax.com/ << My mate David owns n runs car wash n wax
(uk supplier of the Chemical Guys products), you get a 10% discount for being a ClioSport member too.
http://www.seriousperformance.co.uk/ << Another great place to get products, IIRC you get a ClioSport discount there too.
http://www.meguiars.co.uk/
http://www.autoglym.co.uk/index2.html
Cheers, Al.