Im trying to change a certain Mesh Renderers materials. How should i do that correctly?

using UnityEngine;
using System.Collections;

public class Paint : MonoBehaviour {

public Material[] PaintColor;
public MeshRenderer ChangeColor;

public Renderer rend;

void Start () 
{


}

public void Change () 
{

	ChangeColor.materials [1] = PaintColor [0];
	
}

}

(In C# variable names start with lowercase letter)

for change the material color use:

gameObject.renderer.material.color = Color.black;

“black” in this case is like other default colors like .red .white ecc… see here: Color Docs

If you want to be more accurate you can create your RGB color with:

new Color(R, G, B).

where R, G, B are floats from 0.0 to 1.0.

using UnityEngine;
using System.Collections;

public class Paint : MonoBehaviour {

	private MeshRenderer renderer;
	
	void Awake()
	{
		renderer = GetComponent<MeshRenderer>();
	}
	
	public void ChangeTint(Color color)
	{
		renderer.material.color = color;
	}
}