MASTERING
This is an art in itself. Few people have great mastering skills for different styles of music. Mastering can make or break your mix, so be carefull how you approach it.
Mostly following effects are inserted into the master output: multibandcompression, subtle eq, stereo imaging, maximiser and dithering. Those last 2 always should be last in the chain, for the rest U can mingle effects to your likes.