Some key things I kept in mind when designing Barricade is that he is in several iterations: an enforcer, a scout, intimidating, tough, authoritative, his motto is "to punish and enslave", he searched for glasses on eBay once. 

The vehicle I chose for Barricade was a generic black and white police car similar to his Bayverse counterparts black and white Ford Saleen Mustang police car which also has red and blue fog lights cuz I thought it'd complement the siren lights well. While not shown in the character sheet, the Decepticon symbol in his vehicle mode resides on the top of the car behind the siren lights which would end up on his chest in his robot mode. 

When it came to the color, well, yeah, I stuck to the color of most of Barricade's most recent iterations which sport mostly black and white. I also added tidbits of yellow around the headlights and your typical red and blue on the siren lights. When it came to his body, I made it so that Barricade's body was formed to emulate police riot gear. He would communicate his intimidating authoritative nature through his choice of vehicle and makes himself appear like the local law enforcement equipped with gear designed for hostile situations. His torso makes up the vest with the headlight in the center. The siren lights split and placed on both shoulders. The shoulder armor made up of the rear lights. The forearm armor composed of the car doors. Aiming for a riot shield look here and I made his feet and legs look similar to an officer's boots, especially the soles. I placed his wheels on the hips and on his back where his shoulder blades would be. This choice of placement of the design takes inspiration from his G1 counterpart, and I placed the split front grill of the car on his waist. I also gave him an electric baton as his weapon to match his riot police officer look. Also, on a side note, it parallels Bumblebee's stinger. It's all connected! 

For Barricade's face, I gave him a very rigid face. I know it's a bit hard to see with the visor, but if you look close enough, you can see the rigid edges highlighting his hardened demeanor. I gave Barricade a full-on riot police helmet with a tinted visor to conceal most of his facial features to communicate this ominous and threatening vibe, leaving his intense soul peering eyes to be the highlight of the mask, as well as his jagged glowing mouth that shows whenever he talks, or rather whenever he shouts, which noticeably looks similar to Blitzwing's random nutcase personality from Transformers Animated.