Wash the car with any soap you want but the trick is detail spray. I was my car with meguires as well but I just let it dry however. Same company offers a detail/touch up wash that you spray on car wipe in then towel it dry. Takes away any and all spots. Can't remember exact name but the stuff is awesome. If your car still fairly clean you can just spray it down let it dry and hit with that stuff and it makes it look beautiful

 

The last time I washed I ended up drying with detail spray. It helped with the water spots a lot.

 

It always does.