When you decide to use color pencils, it is simple and straight forward. They have to be just taken out of the box and used. The creativity can be expressed through the sketches and the use of different shades. There is not much technique here unless one is into pencil shading, where the strokes and angle at which the pencil is held, etc, matters.
Plain pencils and charcoal sketches are very famous and require a lot of skill and patience to master. This is because, the charcoal tends to stick on to your fingers and hands, from the paper you have drawn on, thus ruining the drawing. The pressure used also matters as it affects the picture drawn.
When one paints or uses thicker colors like crayons or color pens, technique plays a vital role. There is a difference in the outcome when you give the crayon to a 3 year old child and a bigger child who knows how to use the crayon. Here, the angle, the pressure and the type of crayon used makes a difference to the final outcome. Wax crayons will produce a different result when compared to pastels. Though both are packaged similarly and need to be used the same way, the end results vary drastically. This is because the consistencies of these crayons vary.