It's not too hard. Start with the basic shape of the head and body. Then add the details like the eyes, nose, and ears. Sketch the fur lightly to give it texture.
The charm lies in the details. Maybe it's the big eyes of the kitten, or the way it plays and interacts. Also, the colors and style of the cartoon can make it very endearing.
Well, maybe the biker guy notices the kitten in danger on the road and uses his skills to swerve and rescue it. He could also shout to warn others and make sure the area is clear before picking up the kitten.
Well, it might be a tale of how the bulldog and the kitten learn to get along despite their differences. Or it could focus on their funny misadventures in a neighborhood.