One of the most important things you can do when drawing in general is giving objects texture. Texture can be achieved in many ways when drawing or paint such as using different objects to get different texture. Like using your finger or a blending stump to help make your colors appear smoother or help give it depth with shading.
However when doing art digitally you don’t have that option to use different things, you only have your stylus or pen. However this is easily solved with brushes in the software you use to draw. This can be very help full to give object more texture. For example, you could go from a smooth drawing of leaf to one that looks a bit more hand drawn.