Step Number One:
Click on "Online"
Step Number Two
Click on "Team Match"
Step Number Three
Click on "Customize"
Step Number Four
Click on "Outfit"
Step Number Five
Click on "Change Outfit"
Step Number Six
Click on the left arrow next to your third customizable option on which if you keep clicking through you will find a head skin for Wesker, Barry, Jake, Chris and Leon.
Also below you can customize your character with any jammer and shoulder plating you like!