Hi Arnaud. The likeness is pretty good in the final sketch. But some more practice carefully drawing the abstraction would be helpful, I think. Its big problem is the main vertical center line of the face. You drew it projecting far off the front of the face. Or perhaps you just did not draw the eyes and nose rhythms in the proper relationship to the center line. Either way, the center line should represent the front plane of the face. It should touch the entire length of the forehead, then it should touch the septum of the nose, where it meets the upper lip and then should end at the front plane of the chin. And the eyes should sit equal distance from the center line (but with perspective taken into consideration when the head is turned away, as in this drawing). Also, the final sketch does not feel very final. It seems more like a loose rough sketch. Partly because of the problems with your construction, but also because of the quick, spontaneous feeling to the line work. Maybe the quick spontaneous look is what your goal is here. I'm not sure. But if you want to do more realistic painted caricatures, the final drawing should have more attention paid to the quality of the shapes. And you will need to shade them more like a painter and less like an inker. The more you practice tonal drawing techniques, the better prepared you will be to move into color painting.

You could certainly do it that way. It's probably easiest to do a tracing on thin paper or over a light box if using heavier paper. You could also just draw the final drawing on the same paper as the abstraction if you drew the rhythm lines light enough to erase.

Sorry I didn't see this sooner. I would say that the rendering needs a bit more work The halftones look flat, especially in the forehead. The structure of the face is overly rounded, especially the lower half of the face. Find ways to add more straight edges. And yeah the ear is definitely not structured correctly. Be sure to add ear anatomy to your list of things to study. They're actually pretty simple to memorize. But most importantly, I'm afraid that I don't see a very strong likeness in here. I don't know your dad as well as you do. But judging from the photo, it doesn't seem to look like him. You changed the shape of his smile too much so that it doesn't look like his smile. And the shapes of the eyes and nose just don't look like the eyes and nose of the person in the photo. If you haven't done this already, be sure to flip your painting to look at it backwards and you will also notice some bad symmetry in the structure of the head. Caricatures don't always need to be symmetrical. But in this case, it throws off the balance of the head. I hope this doesn't sound too harsh. I can see you have a good hand for painting. You just need to focus on the structure and likeness before moving on to the painting stage.