Change the shoelaces. Most cleats come in basic black with black laces. Change the laces to white or to your team's colors to help them stand out.
Install new spikes. While most cleats come with molded-on spikes, some allow you put your own kind in there. Consider spray painting these different colors to help differentiate them from other spikes or look for spikes that are already different colors.
Add unusual patterns in tape. While most players tape their shoes for protection, some will go the extra mile and make patterns. Hall of Fame running back Lenny Moore got the nickname "Spats" because of the way his cleats looked when taped.
Do some cutting. Some players will cut away at the insoles or the bottom of the cleat to better fit their feet. Because so many cleats are made in the same fashions, players with wider feet will doctor the cleat this way.