You must wash it thoroughly. . getting it off while its still wet is the key. If you can't do that, well, be prepared for the process. Wash it with your car wash soap of choice, this will get the BIG peices off, but be careful not to mar. Next, clay. Clay the SH*T out of it. I've ogne through 10 oz. of soap/water lube just on 1 bird spot before. FInally, start with a very mild polish. I like Clearkote's Vanilla Moose. Polish, and then inspect the work area. If you need to get more aggressive (which you probably will), go to a next higher polish. I step up to Optimum's Polish. That usually gets it. make sure you have hte right ammount of product and APPLICATOR. I use a Porter Cable, but you could do just fine with a regular foam applicator and elbow grease on a small spot.
So to recap:
Wash, Clay, Polish, Wax, ENJOY!