Use carwash with wax on the frame- leaves a wax finish to protect the paint. Use degreaser (citrus ones are best, don't use car degreasers- to harsh) on the chain, wheel rims, cranks and any tough spots of grease on the frame.

We do ours outside either on grass or on concrete with the bike on a repair stand or leaning against a wall. A Chain cleaner machine (plastic body which clips over the chain) is great as you pour the degreaser into the body and use less than pouring it all over the chain.